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This article records new
taxa In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...
of every kind of
fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...
archosaur Archosauria () or archosaurs () is a clade of diapsid sauropsid tetrapods, with birds and crocodilians being the only extant taxon, extant representatives. Although broadly classified as reptiles, which traditionally exclude birds, the cladistics ...
that were scheduled to be described during 2023, as well as other significant discoveries and events related to the
paleontology Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure ge ...
of archosaurs that were published in 2023.


Pseudosuchians


New pseudosuchian taxa


General pseudosuchian research

* Evidence of the impact of the interplay of abiotic and biotic processes on the evolution of pseudosuchians is presented by Payne ''et al.'' (2023). * A study on the biomechanical properties of the skull of '' Riojasuchus tenuisceps'' is published by Taborda, Von Baczko & Desojo (2023), who propose that ''R. tenuisceps'' could have had a wading habit, feeding on small-sizey prey caught from the shoreline. * A study on the bone histology of '' Decuriasuchus quartacolonia'' is published by Farias ''et al.'' (2023), who interpret their findings as indicative of early ontogenetic stage of known specimens, which might have stayed in group to obtain food and avoid predation before reaching maturity, as well as opening the possibility that ''D. quartacolonia'' may represent an earlier growth stage of the larger ''
Prestosuchus chiniquensis ''Prestosuchus'' (meaning "Prestes crocodile") is an extinct genus of pseudosuchian in the group Loricata, which also includes ''Saurosuchus'' and ''Postosuchus''. It has historically been referred to as a "rauisuchian", and was the defining mem ...
''. * A study on the bone
histology Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissue (biology), tissues. Histology is the microscopic counterpart to gross anatomy, which looks at large ...
of '' Fasolasuchus tenax'' and ''Prestosuchus chiniquensis'', providing evidence of slower growth rate in the latter taxon, is published by Ponce ''et al.'' (2023). * A study on the biomechanics of the skull of '' Saurosuchus galilei'' is published by Fawcett ''et al.'' (2023), who interpret ''Saurosuchus'' as having a weak bite for an animal of its size, possessing several mechanically weak features in the skull, and likely avoiding tooth–bone interactions while feeding. * Redescription of the braincase of ''Saurosuchus galilei'' and a study of its sensorial capacities is published by von Baczko ''et al.'' (2023), who report evidence interpreted as indicative of an enhanced olfactory acuity. * An osteoderm and tooth of a 'rauisuchian', likely a
rauisuchid Rauisuchidae is a group of large (up to ) predatory Triassic archosaurs. Some disagreement exists over which genera should be included in the Rauisuchidae and which should be in the related Prestosuchidae and Poposauridae, and indeed whether thes ...
, are described from the lower
Elliot Formation The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup. Outcrops of the Elliot Formation have been found in the northern Eastern Cape, so ...
of South Africa, and identify two potential morphotypes of rauisuchid in the lower Elliot. * Redescription of the anatomy of the skull of ''
Shuvosaurus inexpectatus ''Shuvosaurus'' (meaning "Shuvo hatterjees lizard") is a genus of beaked, bipedal poposauroid pseudosuchian from the Late Triassic (early to middle Norian) of western Texas. Despite superficially resembling a theropod dinosaur, especially the ...
'' is published by Lehane (2023).


Aetosaur research

* A study on the
humeral The humerus (; : humeri) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of ...
histology Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissue (biology), tissues. Histology is the microscopic counterpart to gross anatomy, which looks at large ...
in specimens of ''
Aetosaurus ferratus ''Aetosaurus'' is an extinct genus of pseudosuchian reptile belonging to the order (biology), order Aetosauria. It is generally considered to be the most primitive aetosaur. Three species are currently recognized: ''A. ferratus'', the type specie ...
'' from the Kaltental site (Lower Stubensandstein,
Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...
) is published by Teschner ''et al.'' (2023), who interpret the studied specimens as juveniles, and interpret the accumulation of small-sized specimens at Kaltental as possible evidence of gregarious behavior in juveniles of ''A. ferratus''. * Parker, Reyes & Marsh (2023) describe a new specimen of '' Typothorax coccinarum'' from
Petrified Forest National Park Petrified Forest National Park is a national park of the United States in Navajo and Apache counties in northeastern Arizona. Named for its large deposits of petrified wood, the park covers about , encompassing semi-desert shrub steppe as wel ...
(
Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
) that is the largest aetosaur specimen reported to date, and report that the studied individual likely had not yet reached skeletal maturity, indicating that body size may not be a reliable indicator of maturity in aetosaurs.


Crocodylomorph research

* A study on the bone histology of early crocodylomorphs is published by Botha ''et al.'' (2023), who interpret their findings as indicating that the transition from high growth rates of earlier-diverging pseudosuchians to slower rates of bone deposition during mid-late
ontogeny Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the ovum, egg to adult. The term can also be used to refer to t ...
happened around the origin of Crocodylomorpha during the Late Triassic. * Revision of the fossil material of '' Saltoposuchus connectens'' is published by Spiekman (2023), who considers ''S. connectens'' to be a taxon distinct from '' Terrestrisuchus gracilis'', and interprets the
histology Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissue (biology), tissues. Histology is the microscopic counterpart to gross anatomy, which looks at large ...
of the femur of the second-largest studied specimen as indicative of sustained high growth rates. * Redescription of ''Terrestrisuchus gracilis'' is published by Spiekman ''et al.'' (2023), who report evidence indicative of extensive pneumatization of the posterior skull region, as well as probable anatomical adaptations to non-nocturnal, possibly cathemeral activity patterns. * Evidence from the osteological correlates of the
trigeminal nerve In neuroanatomy, the trigeminal nerve (literal translation, lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for Sense, sensation in the face and motor functions ...
in extant and fossil taxa, interpreted as indicative of an increase in sensory abilities in Early Jurassic crocodylomorphs, preceding their transitions to a semiaquatic habitat, is presented by Lessner ''et al.'' (2023). * A study on the relationship between
osteoderm Osteoderms are bony deposits forming scales, plates, or other structures based in the dermis. Osteoderms are found in many groups of extant and extinct reptiles and amphibians, including lizards, crocodilians, frogs, temnospondyls (extinct amph ...
relative area of pits and terrestrial or aquatic lifestyle in extant and extinct crocodyliforms, indicating that taxa with lower the degree of ornamentation were more likely to be terrestrial, is published by de Araújo Sena & Cubo (2023). * A study on palatal grooves of
thalattosuchia Thalattosuchia is a clade of mostly marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution. They are colloquially referred to as marine crocodiles or sea crocodiles, though they are not member ...
ns is published by Young ''et al.'' (2023), who report that the studied grooves were continuous with ossified canals that connected the oral cavity to the nasal cavity, and interpret the studied grooves and canals as likely evidence of the existence of a heat exchange pathway linking the palatal vascular
plexus In anatomy, a plexus (from the Latin term for 'braid') is a branching network of blood vessels, lymphatic vessels, or nerves. The nerves are typically axons outside the central nervous system. The standard plural form in English is plexuses. Al ...
to the vessels that supplied blood to the brain and eyes. * A study on the growth patterns of ''
Macrospondylus bollensis ''Macrospondylus'' is an extinct genus of machimosaurid teleosauroid crocodyliform from the Early Jurassic (Toarcian) of Europe. Fossils are known from the Posidonia Shale of Germany, the Whitby Mudstone of the United Kingdom, and the "'' schi ...
'' is published by Johnson, Amson & Maxwell (2023). * Young ''et al.'' (2023) describe thalattosuchian fossil material from deposits in European
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
ranging from
Bajocian In the geologic timescale, the Bajocian is an age and stage in the Middle Jurassic. It lasted from approximately 170.9 ±0.8 Ma to around 168.2 ±1.2 Ma (million years ago). The Bajocian Age succeeds the Aalenian Age and precedes the Bathonia ...
to
Berriasian In the geological timescale, the Berriasian is an age/ stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 143.1 ±0.6 Ma and 137.05 ± 0.2 (million years ago) ...
or
Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 137.05 ± 0.2 Ma and 132.6 ± 0.2 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretac ...
in age, including fossil material of
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
''
Thalattosuchus ''Thalattosuchus'' is an extinct genus of marine crocodyliformes, crocodyliform that lived in the oceans during the Middle Jurassic, Middle to Late Jurassic. Though the genus ''Thalattosuchus'' itself was named in 2020, its fossils have historic ...
'', '' Torvoneustes'' and '' Tyrannoneustes'' which expands known geographical range of these taxa, as well as including the oldest record of Geosaurini reported to date. * Revision of the fossil record of thalattosuchians from the Jurassic Rosso Ammonitico Veronese (
Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...
), as well as description of three new
metriorhynchoid Metriorhynchoidea is an extinct superfamily (biology), superfamily of thalattosuchian crocodyliforms from the Early Jurassic to the Early Cretaceous (Toarcian - Valanginian, possibly as late as early Aptian) of Europe, North America and South Ame ...
specimens (including a specimen from the upper Bajocian-upper Bathonian of Cima del Porco representing one of the oldest known metriorhynchids, and a Bajocian specimen which might have beaan a metriorhynchid or a closely related metriorhynchoid), is published by Serafini ''et al.'' (2023). * Evidence indicative of limited
evolutionary convergence Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last comm ...
in the morphology of the postcranial skeletons of members of Thalattosuchia and Dyrosauridea, even when found within similar environments, is presented by Scavezzoni & Fischer (2023). * New specimen of '' Hsisosuchus'' of uncertain specific assignment, providing new information on the shape and arrangement of the osteoderms in the ventral trunk shield of members of this genus, is described from the Upper Jurassic of Yunnan (
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
) by Wu ''et al.'' (2023). * A study on the notosuchian physiology is published by de Araújo Sena ''et al.'' (2023), who find maximal rates of oxygen consumption of notosuchians to be lower than those of extant mammals and monitor lizards but higher than those of extant crocodilians during periods of intensive activity, and interpret notosuchians as likely having a more active lifestyle than extant crocodilians. * A study on possible effects of climate, body size and diet on the survival of terrestrial notosuchians during the
Cretaceous–Paleogene extinction event The Cretaceous–Paleogene (K–Pg) extinction event, also known as the K–T extinction, was the extinction event, mass extinction of three-quarters of the plant and animal species on Earth approximately 66 million years ago. The event cau ...
is published by Aubier ''et al.'' (2023), who find evidence of increase in body size during the Late Cretaceous which may be related to the shift from omnivorous to carnivorous diet, but find the studied data insufficient to list definitive reasons for the survival of
sebecids Sebecidae is an extinct family of prehistoric terrestrial sebecosuchian crocodylomorphs, known from the Late Cretaceous and Cenozoic of Europe and South America. They were the latest surviving group of non-crocodilian crocodylomorphs. The oldest ...
into the Cenozoic. * A study on the bone histology of a
femur The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femo ...
of ''
Araripesuchus wegeneri ''Araripesuchus'' is a genus of extinct crocodyliform that existed during the Cretaceous period of the late Mesozoic era some 125 to 66 million years ago. ''Araripesuchus'' is generally considered to be a notosuchian (belonging to the clade Mesoe ...
'' is published by Faure-Brac & Cubo (2023), who find no evidence for the presence of sustained fibrolamellar complex in the studied taxon, and interpret this finding as consistent with the
ectotherm An ectotherm (), more commonly referred to as a "cold-blooded animal", is an animal in which internal physiological sources of heat, such as blood, are of relatively small or of quite negligible importance in controlling body temperature.Dav ...
ic regime inferred for notosuchians, but not with their high maximum metabolic rates and with upright stance of ''A. wegeneri'', which therefore had a
phenotype In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological propert ...
with no equivalent in the extant fauna. * A study on the long bone microstructure in ''
Notosuchus terrestris ''Notosuchus'' (; 'southern crocodile') is an extinct genus of South American notosuchian crocodyliforms. It was terrestrial, living approximately 85 million years ago in the Santonian stage of the Late Cretaceous. Description ''Notosuchus'' ...
'', providing evidence of high growth rates interrupted by periods of decreased or arrested growth, is published by Navarro, Cerda & Pol (2023). * A study on the bone histology of '' Stratiotosuchus maxhechti'', interpreted as indicative of growth dynamics similar to those of medium-to-large theropods, is published by Andrade ''et al.'' (2023), who argue that niche partitioning between
baurusuchids Baurusuchidae is a Gondwanan Family (biology), family of mesoeucrocodylians that lived during the Late Cretaceous. It is a group of terrestrial hypercarnivorous crocodilians from South America (Argentina and Brazil) and possibly Pakistan. Baurusu ...
and theropods was more likely than competitive exclusion. * Description of new fossil material of itasuchid crocodyliforms from the Upper Cretaceous Bauru Group (
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
) is published by Pinheiro ''et al.'' (2023), who also confirm the
monophyly In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent comm ...
of Itasuchidae with some variation in its content, and find the South American itasuchid species to occupy a crocodyliform morphospace, possibly indicating distinct niche occupations. * A new mandibular ramus referred to '' Hamadasuchus cf. reboulli'' is described by Pochat-Cottilloux ''et al.'', who propose an emended diagnosis of the taxon and argue that only three specimens are actually referrable to this species. They further discuss multiple anatomical characters of the mandible that they suggest represent intraspecific or ontogenetic differences and are not diagnostically valuable. As a consequence, it is suggested that ''
Antaeusuchus ''Antaeusuchus taouzensis'' is a species of peirosaurid notosuchian from the Late Cretaceous Kem Kem Group of Morocco. It was described in 2021, and it is the only species in the genus ''Antaeusuchus''. It is the fourth notosuchian described fro ...
'' may be a species of ''Hamadasuchus''. * Pochat-Cottilloux ''et al.'' (2023) describe the endocranial structures of ''Hamadasuchus'', providing evidence of adaptations to terrestrial lifestyle. * A study on the ecology of
sebecids Sebecidae is an extinct family of prehistoric terrestrial sebecosuchian crocodylomorphs, known from the Late Cretaceous and Cenozoic of Europe and South America. They were the latest surviving group of non-crocodilian crocodylomorphs. The oldest ...
from the Paleocene locality of Tiupampa (
Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...
), using a multi-isotopic proxy approach, is published by Pochat-Cottilloux ''et al.'' (2023), who interpret their findings as indicative of
ectotherm An ectotherm (), more commonly referred to as a "cold-blooded animal", is an animal in which internal physiological sources of heat, such as blood, are of relatively small or of quite negligible importance in controlling body temperature.Dav ...
ic thermoregulation and terrestrial lifestyle in the studied crocodylomorphs. * A study on the
biogeography Biogeography is the study of the species distribution, distribution of species and ecosystems in geography, geographic space and through evolutionary history of life, geological time. Organisms and biological community (ecology), communities o ...
of
neosuchia Neosuchia is a clade within Mesoeucrocodylia that includes all modern extant crocodilians and their closest fossil relatives. It is defined as the most inclusive clade containing all Crocodylomorpha, crocodylomorphs more closely related to ''Croc ...
ns throughout their evolutionary history, providing evidence of the impact of saltwater tolerance of neosuchians from different subclades on their historical biogeography, is published by Groh ''et al.'' (2023). * Description of a new specimen of '' Acynodon adriaticus'' from the
Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...
Villaggio del Pescatore site (
Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...
) and a study on the affinities of this species is published by Muscioni ''et al.'' (2023). * Revision of the fossil material of
Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...
crocodyliforms from the Arlington Archosaur Site (
Woodbine Group The Woodbine Group is a geological formation in east Texas whose strata date back to the Early to Middle Cenomanian age of the Late Cretaceous. It is the producing formation of the giant East Texas Oil Field (also known as the "Black Giant") from ...
;
Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
), providing evidence of the presence of at least five taxa with different snout shapes and body size which might be related to niche partitioning, is published by Adams, Drumheller & Noto (2023). * A study on the taxonomic diversity, phylogenetic relationships and evolutionary history of
Australasia Australasia is a subregion of Oceania, comprising Australia, New Zealand (overlapping with Polynesia), and sometimes including New Guinea and surrounding islands (overlapping with Melanesia). The term is used in a number of different context ...
n crocodyliforms is published by Ristevski ''et al.'' (2023). * Venczel (2023) describes new fossil material of '' Diplocynodon kochi'' from the Eocene Transylvanian Basin (
Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...
), extending known fossil record of this species to four new localities. * A tooth of a member of the genus ''
Purussaurus ''Purussaurus'' is an extinct genus of giant caiman that lived in South America during the Miocene epoch, from the Friasian to the Huayquerian in the SALMA classification. It is known from skull material found in the Brazilian and Peruvian Am ...
'' is described from the Toma Vieja locality near Paraná City (traditionally considered as the base of Ituzaingó Formation) by Bona ''et al.'' (2023), representing the first record of this genus from the Late Miocene of
Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
and the southernmost occurrence of a member of this genus reported to date. * Taxonomic revision of the genus ''
Mourasuchus ''Mourasuchus'' is an extinct genus of giant, aberrant caiman from the Miocene of South America. Its skull has been described as duck-like, being broad, flat, and very elongate, superficially resembling '' Stomatosuchus'' from the Late Cretace ...
'' is published by Cidade & Hsiou (2023). * A study on the neuroanatomy and phylogenetic affinities of '' Portugalosuchus azenhae'' is published by Puértolas-Pascual ''et al.'' (2023), who recover ''Portugalosuchus'' as a member of
Gavialoidea Gavialoidea is one of three superfamily (zoology), superfamilies of crocodylians, the other two being Alligatoroidea and Crocodyloidea. Although many extinct species are known, only the gharial ''Gavialis gangeticus'' and the false gharial ''Tomi ...
most closely related to ''
Thoracosaurus neocesariensis ''Thoracosaurus'' (chest lizard) is an extinct genus of long-snouted eusuchian which existed during the Late Cretaceous and Early Paleocene in North America and Europe. Taxonomy ''Thoracosaurus'' had traditionally been thought to be related to ...
''. *A collection of isolated gavialoid teeth is reported from the shallow marine deposits of Eocene
Turnu Roșu Turnu Roșu (; ) is a commune located in Sibiu County, Transylvania, Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, ...
(Romania) by Venczel ''et al.'' (2023), who recognize a minimum of five morphotypes. * Burke & Mannion (2023) present a reconstruction of the neuroanatomy and neurosensory apparatus of ''"Tomistoma" dowsoni'', providing evidence that this gavialoid displayed an intermediate morphology between those of extant
gharial The gharial (''Gavialis gangeticus''), also known as gavial or fish-eating crocodile, is a crocodilian in the family (biology), family Gavialidae and among the longest of all living crocodilians. Mature females are long, and males . Adult males ...
s and
false gharial The false gharial (''Tomistoma schlegelii''), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the Family (biology), family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It ...
s. * Redescription of ''"Tomistoma" taiwanicus'' is published by Cho & Tsai (2023), who transfer this species to the genus ''
Toyotamaphimeia ''Toyotamaphimeia'' (named after Toyotama-hime) is a genus of extinct gavialid crocodylian which lived in Japan and Taiwan during the Middle Pleistocene. A specimen recovered in 1964 at Osaka University during the construction of a new science bu ...
''. * A study on the inner braincase anatomy of ''
Voay robustus ''Voay'' is an extinct genus of crocodile from Madagascar that lived during the Late Pleistocene to Holocene, containing only one species, ''V. robustus''. Numerous subfossils have been found, including complete skulls, noted for their distinctiv ...
'' is published by Perrichon ''et al.'' (2023). *A collection of eighteen isolated
neosuchian Neosuchia is a clade within Mesoeucrocodylia that includes all modern extant crocodilians and their closest fossil relatives. It is defined as the most inclusive clade containing all crocodylomorphs more closely related to ''Crocodylus niloticus' ...
teeth as well as a single isolated crocodyliform osteoderm are reported from the Berriasian–Valanginian Feliz Deserto Formation (
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
) by Lacerda ''et al.'' (2023), who recognize a minimum of three morphotypes among the teeth. * A collection of 55
coprolite A coprolite (also known as a coprolith) is fossilized feces. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour (in this case, diet) rather than morphology. The name ...
s from the Eocene Na Duong Basin (
Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...
) are described by Halaçlar ''et al''. (2023), who interpret them as belonging to a new
ichnotaxon An ichnotaxon (plural ichnotaxa) is "a taxon based on the fossilized work of an organism", i.e. the non-human equivalent of an artifact. ''Ichnotaxon'' comes from the Ancient Greek (''íchnos'') meaning "track" and English , itself derived from ...
, '' Crococopros naduongensis''


Non-avian dinosaurs


New dinosaur taxa


General non-avian dinosaur research

* Schwarz ''et al''. (2023) observe the contents of unopened containers from
Tendaguru Formation The Tendaguru Formation, or Tendaguru Beds are a highly List of fossiliferous stratigraphic units in Tanzania, fossiliferous Lithostratigraphy, formation and Lagerstätte located in the Lindi Region of southeastern Tanzania. The formation represe ...
(
Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...
) expeditions via CT scans, and indicate the presence of fossils belonging to dinosaurs including '' Dysalotosaurus'', ''
Kentrosaurus ''Kentrosaurus'' ( ; ) is a genus of stegosaurid dinosaur from the Late Jurassic in Lindi Region of Tanzania. The type species is ''K. aethiopicus'', named and described by German people, German Palaeontology, palaeontologist Edwin Hennig in 191 ...
'', and ''
Giraffatitan ''Giraffatitan'' (name meaning "titanic giraffe") is a genus of sauropod dinosaur that lived during the late Jurassic Period (geology), Period (Kimmeridgian–Tithonian stages) in what is now Lindi Region, Tanzania. Only one species is known, ...
''. * A study on causes of recovery of different interrelationships of the three major dinosaur clades (Theropoda, Sauropodomorpha, and Ornithischia) in phylogenetic studies is published by Černý & Simonoff (2023), who find the three possible ways of resolving the relationships among these lineages (Saurischia-Ornithischia, Ornithischiformes-Theropoda and Ornithoscelida-Sauropodomorpha dichotomies) to be statistically indistinguishable and supported by nearly equal numbers of characters in the datasets from the studies of Baron, Norman & Barrett (2017) and Langer ''et al.'' (2017). * A review of the history of morphometric studies in non-avian dinosaurs is published by Hedrick (2023). * Cullen ''et al.'' (2023) reevaluate evidence for anomalously positive stable carbon isotope compositions of dinosaur bioapatite, report that the studied anomaly is present in the carbon isotope compositions of bioapatite in
tooth enamel Tooth enamel is one of the four major Tissue (biology), tissues that make up the tooth in humans and many animals, including some species of fish. It makes up the normally visible part of the tooth, covering the Crown (tooth), crown. The other ...
of not only dinosaurs but also mammals and crocodilians and in scale ganoine of
gar Gars are an ancient group of ray-finned fish in the family Lepisosteidae. They comprise seven living species of fish in two genera that inhabit fresh, brackish, and occasionally marine waters of eastern North America, Central America and Cuba ...
s from the "Rainy Day Site" in the
Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...
Oldman Formation The Oldman Formation is a stratigraphic unit of Late Cretaceous (Campanian stage) age that underlies much of southern Alberta, Canada. It consists primarily of sandstones that were deposited in fluvial channel and floodplain environments. It was ...
(
Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...
,
Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
) but is absent in extant vertebrates from the near-analogue modern ecosystem in the
Atchafalaya Basin The Atchafalaya Basin, or Atchafalaya Swamp (; Louisiana French: ''Atchafalaya'', ), is the largest wetland and swamp in the United States. Located in south central Louisiana, it is a combination of wetlands and river delta area where the Atch ...
(
Louisiana Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...
, United States), and interpret their findings as indicating that the studied anomaly is not the result of a unique dietary physiology of dinosaurs. * A study on the element ratios in the enamel of dinosaurs from the Oldman Formation is published by Cullen & Cousens (2023), who interpret their findings as indicative of differences in habitat use, dietary plant sources and feeding height between hadrosaurs and other ornithischians, as well as indicating that troodontid theropods were mixed-feeding to plant-dominant omnivores. * Dinosaur eggshell fragments with preserved eggshell membranes are reported from the
Late Jurassic The Late Jurassic is the third Epoch (geology), epoch of the Jurassic Period, and it spans the geologic time scale, geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic stratum, strata.Owen ...
Brushy Basin Member of the
Morrison Formation The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltston ...
(
Utah Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
) by Lazer ''et al.'' (2023). * Oussou ''et al.'' (2023) describe new tracksites with ornithopod, sauropod and theropod (including possible bird-like non-avian theropod) tracks from the Jurassic Isli Formation (
Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...
). * Navarro-Lorbés ''et al.'' (2023) describe tracks produced by an undetermined bipedal non-avian dinosaur from the Lower Cretaceous Cameros Basin (
Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
), interpreted as likely produced during swimming, and provide information on the swimming behaviour of the trackmaker. * Méndez Torrez ''et al.'' (2023) report the discovery of the first assemblage of dinosaur tracks (dominated by sauropod tracks, including tracks of possible non-
neosauropod Neosauropoda is a clade within Dinosauria, coined in 1986 by Argentine paleontologist José Bonaparte and currently described as '' Saltasaurus loricatus'', '' Diplodocus longus'', and all animals directly descended from their most recent common a ...
eusauropods, and possibly preserving evidence of herd behaviour) from the Jurassic to earliest Cretaceous Castellón Formation (
Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...
). * Naimi ''et al.'' (2023) describe tracks of small theropods and ornithopods from the
Albian The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/s ...
-
Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...
strata from the Ouled Nail Mounts, representing some of the stratigraphically youngest records of non-avian dinosaurs in
Algeria Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Alger ...
reported to date. * Esperante ''et al.'' (2023) report the discovery of a short-lived new site with hundreds of tracks of dinosaurs (subsequently removed because of the construction of a new road) from the El Molino Formation (Bolivia), including swim traces of theropod dinosaurs. *Description of four dinosaur teeth assignable to three different groups (
Tyrannosauroidea Tyrannosauroidea (meaning 'tyrant lizard forms') is a superfamily (or clade) of coelurosaurian theropod dinosaurs that includes the family Tyrannosauridae as well as more basal relatives. Tyrannosauroids lived on the Laurasian supercontinent ...
,
Titanosauriformes Macronaria is a clade of sauropod dinosaurs. Macronarians are named after the large diameter of the nasal opening of their skull, known as the external naris, which exceeded the size of the orbit, the skull opening where the eye is located (hence ...
, and
Hadrosauroidea Hadrosauroidea is a clade or superfamily of ornithischian dinosaurs that includes the "duck-billed" dinosaurs, or Hadrosauridae, and all dinosaurs more closely related to them than to ''Iguanodon''. Their remains have been recovered in Asia, Euro ...
) from the Cretaceous Sunjiawan Formation (
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
) is published by Yin ''et al''. (2023), representing the first record of a theropod from the formation, as well as representing potentially two new taxa, as the hadrosauroid teeth are distinct from '' Shuangmiaosaurus''. * A review of the
Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...
dinosaur fauna from
Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...
is published by Samathi ''et al.'' (2023). * Li ''et al.'' (2023) report the discovery of sauropod and ornithopod tracks from the Zonggei Formation, providing evidence for the presence of abundant dinosaurs in the Late Cretaceous of the Tibet region (China). * Flannery-Sutherland ''et al.'' (2023) describe the first dinosaur tracks from the Upper Cretaceous Nichkesaisk Formation (
Kyrgyzstan Kyrgyzstan, officially the Kyrgyz Republic, is a landlocked country in Central Asia lying in the Tian Shan and Pamir Mountains, Pamir mountain ranges. Bishkek is the Capital city, capital and List of cities in Kyrgyzstan, largest city. Kyrgyz ...
), probably produced by both large-bodied and smaller-bodied theropods or ornithopods. * A study on the duration of Late Cretaceous megaherbivore dinosaur assemblage zones in the 100 m thick stratigraphic section exposed at Dinosaur Provincial Park (Alberta, Canada) is published by Eberth ''et al.'' (2023), who interpret their findings as indicating that the dinosaur assemblage zones in the studied section had duration time of ~600–700.000 years, and were significantly shorter than those in the overlying
Horseshoe Canyon Formation The Horseshoe Canyon Formation is a stratigraphic unit of the Western Canada Sedimentary Basin in southwestern Alberta. It takes its name from Horseshoe Canyon, an area of badlands near Drumheller. The Horseshoe Canyon Formation is part of th ...
. * Review of the Cretaceous non-avian dinosaur egg record from the Gobi Desert of
Mongolia Mongolia is a landlocked country in East Asia, bordered by Russia to the north and China to the south and southeast. It covers an area of , with a population of 3.5 million, making it the world's List of countries and dependencies by po ...
, including descriptions of eggs representing six
ootaxa Egg fossils are the fossilized remains of eggs laid by ancient animals. As evidence of the physiological processes of an animal, egg fossils are considered a type of trace fossil. Under rare circumstances a fossil egg may preserve the remains of t ...
(''
Coralloidoolithus ''Coralloidoolithus'' is an oogenus of dinosaur egg from the Tiantai Basin in Zhejiang Province, containing a single known oospecies ''C. shizuiwanensis''. Formerly, it was classified in the oogenus ''Paraspheroolithus''; however, it was consider ...
'' oosp., ''
Dendroolithus ''Dendroolithus'' is an oogenus of Dendroolithid dinosaur egg found in the late Cenomanian Chichengshan Formation ( Tiantai Group), in the Gong-An-Zhai and Santonian Majiacun Formations of China and the Maastrichtian Nemegt and Campanian B ...
'' oosp., ''
Macroelongatoolithus ''Macroelongatoolithus'' is an oogenus of large theropod dinosaur eggs, representing the eggs of giant caenagnathid oviraptorosaurs. They are known from Asia and from North America. Historically, several oospecies have been assigned to ''Macroelo ...
'' oosp., '' Paraspheroolithus irenensis'',
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
'' Protoceratopsidovum minimum'', and cf. '' Spheroolithus maiasauroides'') from the Upper Cretaceous localities Altan Uul I, Altan Uul IV, Bayanshiree, Shine Us Khudag and Shiluut Uul, is published by Tanaka ''et al.'' (2023). * A study on the stable oxygen and carbon isotope compositions of dinosaur eggshell calcites and tooth apatites from the Upper Cretaceous
Kakanaut Formation The Kakanaut Formation is a geological formation in Siberia, whose strata date back to the Late Cretaceous (Maastrichtian). Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel et al., 2004, pp.593-600 The ...
(
Chukotka Autonomous Okrug Chukotka ( ; ), officially the Chukotka Autonomous Okrug, is the easternmost federal subjects of Russia, federal subject of Russia. It is an Autonomous okrugs of Russia, autonomous okrug situated in the Russian Far East, and shares a border wi ...
,
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
) is published by Amiot ''et al.'' (2023), who interpret their findings as indicating that near-polar Kakanaut dinosaurs likely laid eggs in early spring, giving time for the hatchlings to grow before winter. *A review of Cretaceous dinosaurs from India published by Khosla and Lucas (2023).


Saurischian research

* An isolated ilium of a probable non-
herrerasaurid Herrerasauridae is a family of carnivorous dinosaurs, possibly basal to either theropods or even all of saurischians, or even their own branching from Dracohors, separate from Dinosauria altogether. They are among the oldest known dinosaurs, fi ...
herrerasauria Saurischia ( , meaning "reptile-hipped" from the Greek ' () meaning 'lizard' and ' () meaning 'hip joint') is one of the two basic divisions of dinosaurs (the other being Ornithischia), classified by their hip structure. Saurischia and Ornithis ...
n, potentially representing the first record of such a saurischian in unambiguous
Carnian The Carnian (less commonly, Karnian) is the lowermost stage (stratigraphy), stage of the Upper Triassic series (stratigraphy), Series (or earliest age (geology), age of the Late Triassic Epoch (reference date), Epoch). It lasted from 237 to 227.3 ...
beds, is described from the Pivetta site (Candelária Sequence;
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
) by Garcia ''et al.'' (2023). * Silva ''et al.'' (2023) described new herrerasaurid material from the Predebon site (Candelária Sequence of the Santa Maria Supersequence, Brazil), and interpret its anatomy as possibly indicative of the presence of a herrerasaurid
morphotype In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative ''phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the s ...
distinct from '' Gnathovorax cabreirai'' and '' Staurikosaurus pricei''. * A track site of dinosaur footprints is described from the
Middle Jurassic The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relativel ...
Xietan Formation (
Hubei Hubei is a province of China, province in Central China. It has the List of Chinese provincial-level divisions by GDP, seventh-largest economy among Chinese provinces, the second-largest within Central China, and the third-largest among inland ...
,
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
) by Xing ''et al''. (2023), who interpret the tracks as belonging to small sauropods (similar to ''
Brontopodus ''Brontopodus'' is an ichnogenus of dinosaur footprint by sauropod trackmaker. This ichnogenus is mainly characterized by a wide-gauge trackway, which is distinguishable from narrow-gauge sauropod tracks like '' Breviparopus'' or '' Parabrontopod ...
'') and probable theropods. * Lei ''et al.'' (2023) report theropod bite traces on 68 sauropod bones from the Upper Jurassic
Morrison Formation The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltston ...
(
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
), as well as evidence of tooth wear in large-bodied theropods from the Morrison Formation interpreted as indicating that the studied theropods were biting into bone, and consider it most likely that the wear seen on large theropod teeth was mostly caused by contact with the destroyed bones of the more frequently consumed juvenile sauropods, while the studied bite traces were most likely caused by scavenging on carcasses of large-bodied sauropods.


Theropod research

* A study on the developmental strategies underlying the evolution of body size of non-avialan theropods is published by D'Emic ''et al.'' (2023), who report that changes in the rate and duration of growth contributed nearly equally to the body size changes. * A study on the relationship between the body size of theropods, the area of muscles important for their balance and locomotion, and their capacity for agility is published by Henderson (2023), who argues that theropod body plan had an upper size limit based on a minimum acceleration threshold. * Cullen ''et al.'' (2023) use multiple lines of evidence, including
histology Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissue (biology), tissues. Histology is the microscopic counterpart to gross anatomy, which looks at large ...
of teeth and morphological comparisons, to evaluate proposed theropod facial reconstructions, and argue that non-avian theropods most likely had lips that covered their teeth. * Review of hand modifications and hand functions in late non-avian theropods is published by Barsbold (2023). * Kirmse ''et al.'' (2023) describe a coelophysoid femur from the Tytherington fissures near
Bristol Bristol () is a City status in the United Kingdom, cathedral city, unitary authority area and ceremonial county in South West England, the most populous city in the region. Built around the River Avon, Bristol, River Avon, it is bordered by t ...
, UK, which cannot be definitively compared and referred to ''
Pendraig ''Pendraig'' (meaning "chief dragon" in Middle Welsh) is a genus of coelophysoid theropod dinosaur from South Wales. It contains one species, ''Pendraig milnerae'', named after Angela Milner. The specimen was discovered in the Pant-y-Ffynnon Quarr ...
''. * Peng ''et al.'' (2023) describe abundant tracks from the Upper Triassic Tianquan track site ( Xujiahe Formation; Ya'an, western Sichuan Basin,
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
), interpreted as produced by small theropods and representing one of the earliest record of dinosaurs from the eastern Tethys realm. * New specimen of ''
Sinosaurus triassicus ''Sinosaurus'' (meaning "Chinese lizard") is an extinct genus of basal theropod dinosaur which lived during the Early Jurassic (Hettangian-Sinemurian). Fossils of the animal have been found in the Lufeng Formation, in the Yunnan Province of Chin ...
'', including a complete skull and 11 cervical vertebrae, is described by Zhang, Wang & You (2023). * Purported "
coelophysoid Coelophysoidea is an extinct clade of theropod dinosaurs common during the Late Triassic and Early Jurassic periods. They were widespread geographically, probably living on all continents. Coelophysoids were all slender, carnivorous forms with a ...
-
grade Grade most commonly refers to: * Grading in education, a measurement of a student's performance by educational assessment (e.g. A, pass, etc.) * A designation for students, classes and curricula indicating the number of the year a student has reach ...
" tibia from the
Sinemurian In the geologic timescale, the Sinemurian is an age (geology), age and stage (stratigraphy), stage in the Early Jurassic, Early or Lower Jurassic epoch (geology), Epoch or series (stratigraphy), Series. It spans the time between 199.5 ±0.3 annu ...
of the Isle of Skye (Scotland, United Kingdom) is reinterpreted as fossil material of
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
'' Sarcosaurus woodi'' by
Ezcurra Ezcurra is a surname. Notable people with the surname include: * Alma Ezcurra (born 1986), Spanish politician * Bautista Ezcurra (born 1995), Argentine rugby union player * Encarnación Ezcurra (1795–1838), Argentine political activist * Exequiel ...
''et al.'' (2023). * Sharma, Hendrickx & Singh (2023) describe dental material of a non-coelurosaur
averostra Theropoda (; from ancient Greek , (''therion'') "wild beast"; , (''pous, podos'') "foot"">wiktionary:ποδός"> (''pous, podos'') "foot" is one of the three major groups (clades) of dinosaurs, alongside Ornithischia and Sauropodomor ...
n theropod from the
Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...
Fort Member of the
Jaisalmer Formation The Jaisalmer Formation is a Middle to Late Jurassic-aged geologic formation located in India near the city of Jaisalmer that consists mainly of marine deposits. The formation was first identified and defined by geologist Richard Dixon Oldham in ...
(
India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
), providing evidence of the presence of at least one taxon of a medium to large-bodied theropod on the Tethyan coast of India during the Middle Jurassic. * Tracks assigned to the ichnotaxon
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
''
Eubrontes ''Eubrontes'' is the name of fossilised dinosaur footprints dating from the Late Triassic and Early Jurassic. They have been identified from France, Poland, Slovakia, Czech Republic, Italy, Spain, Sweden, Australia (Queensland), US, India, China ...
'', providing evidence of the presence of small theropods within the Hami pterosaur fauna, are described from the Lower Cretaceous
Tugulu Group The Tugulu Group () is a geological Group in Xinjiang, China whose strata date back to the Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the ...
(Xinjiang, China) by Li ''et al.'' (2023). * Footprints of small theropods with a cursorial gait are described from the Lower Cretaceous Botucatu Formation (
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
) by Leonardi ''et al.'' (2023), who name a new ichnotaxon '' Farlowichnus rapidus''. * Theropod scrapes from the Cretaceous of
Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...
, originally interpreted as evidence of display arenas or leks of theropods, are argued to be more likely results of failed attempts by theropods to dig near-circular bowls that were to be used as nests by Moklestad &
Lucas Lucas or LUCAS may refer to: People * Lucas (surname) * Lucas (given name) Arts and entertainment * Luca Family Singers, or the Lucas, a 19th-century African-American singing group * Lucas, a 1960s Swedish pop group formed by Janne Lucas Perss ...
(2023). * Review of the fossil record of Abelisauroidea in continental Africa is published by Souza-Júnior ''et al.'' (2023). * Averianov & Lopatin (2023) describe an elongated and highly pneumatized cervical vertebra of a long-necked theropod from the Lower Cretaceous (Aptian)
Ilek Formation The Ilek Formation is a Lower Cretaceous geologic Formation (geology), formation in Western Siberia. Many different fossils have been recovered from the formation. It overlies the Late Jurassic Tyazhin Formation and underlies the Albian Kiya Form ...
(
Kemerovo Oblast Kemerovo Oblast (, ), also known as Kuzbass (, ), after the Kuznetsk Basin, is a federal subjects of Russia, federal subject of Russia (an oblast). Kemerovo is the administrative center and largest city of the oblast. Kemerovo Oblast is one of Rus ...
,
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
); subsequently Averianov ''et al.'' (2024) interpret this vertebra as likely belonging to the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
specimen of the noasaurid '' Kiyacursor longipes''. * Barbosa ''et al.'' (2023) study the functional morphology of dental and pedal elements of the skeleton of '' Vespersaurus paranaensis'', and interpret it as indicating that this theropod had a generalist diet, feeding on small or immobile prey. * Amudeo-Plaza ''et al.'' (2023) interpret a theropod tooth from the Cretaceous (Albian-Turonian) Quebrada La Totora Beds as the first record of an
abelisaurid Abelisauridae (meaning "Abel's lizards") is a family (or clade) of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are foun ...
from
Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...
. * Paulina-Carabajal ''et al.'' (2023) report the discovery of a natural cranial
endocast An endocast is the internal cast of a hollow object, often referring to the cranial vault in the study of brain development in humans and other organisms. Endocasts can be artificially made for examining the properties of a hollow, inaccessible ...
of an abelisaurid from the
Santonian The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya ( million years ago) and 83.6 ± 0.7 m ...
Bajo de la Carpa Formation The Bajo de la Carpa Formation is a geologic formation of the Neuquén Basin that outcrop, crops out in northern Patagonia, in the provinces of Río Negro Province, Río Negro and Neuquén Province, Neuquén, Argentina. It is the oldest of two for ...
(
Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
). * Longrich ''et al.'' (2023) describe new abelisaurid material from the
Ouled Abdoun Basin The Oulad Abdoun Basin (also known as the Ouled Abdoun Basin or Khouribga Basin) is a phosphate sedimentary basin located in Morocco, near the city of Khouribga. It is the largest in Morocco, comprising 44% of Morocco's phosphate reserves, and at ...
, interpreted as indicative of coexistence of as many as three abelisaurid taxa in
Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...
during the late
Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...
. * Description of the anatomy of the axial skeleton of ''
Aucasaurus garridoi ''Aucasaurus'' is a genus of medium-sized Abelisauridae, abelisaurid theropod dinosaur from Argentina that lived during the Late Cretaceous (Santonian to Campanian faunal stage, stage) of the Anacleto Formation. It was smaller than the related '' ...
'' is published by Baiano ''et al.'' (2023). * A study on the evolution of the morphological characters of the pelvic girdle, femur, tibia and fibula in early theropods, especially in megalosauroids, is published by Lacerda, Bittencourt & Hutchinson (2023). * Lacerda, Bittencourt & Hutchinson (2023) present reconstructions of the hindlimb musculature of '' Condorraptor currumili'', ''
Marshosaurus bicentesimus ''Marshosaurus'' is a genus of medium-sized carnivorous Theropoda, theropod dinosaur, belonging to the family Piatnitzkysauridae, from the Late Jurassic Morrison Formation of Utah and possibly Colorado. Discovery and naming During the 1960s, o ...
'' and '' Piatnitzkysaurus floresi''. * Revision of the
spinosaurid Spinosauridae (or spinosaurids) is a clade or Family (taxonomy), family of tetanuran theropod dinosaurs comprising ten to seventeen known genera. Spinosaurid fossils have been recovered worldwide, including Africa, Europe, South America, and Asia. ...
taxonomy is published by Terras ''et al.'' (2023). * Pedal ungual
phalanx The phalanx (: phalanxes or phalanges) was a rectangular mass military formation, usually composed entirely of heavy infantry armed with spears, pikes, sarissas, or similar polearms tightly packed together. The term is particularly used t ...
of a possible spinosaurid is described from the Jurassic (
Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...
)
Jaisalmer Formation The Jaisalmer Formation is a Middle to Late Jurassic-aged geologic formation located in India near the city of Jaisalmer that consists mainly of marine deposits. The formation was first identified and defined by geologist Richard Dixon Oldham in ...
(
India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
) by Sharma,
Novas A nova ( novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", Latin for "new") that slowly fades over weeks or months. All observed novae involve white d ...
& Singh (2023). * A collection of seven isolated spinosaurid teeth as well as a single preungual pedal phalanx of an indeterminate theropod are reported from the Berriasian–Valanginian Feliz Deserto Formation (Brazil) by Lacerda ''et al''. (2023). * An isolated spinosaurid tooth of uncertain provenance, likely recovered from a
Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 137.05 ± 0.2 Ma and 132.6 ± 0.2 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretac ...
exposure of the Hastings Group (
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
), is assigned to a taxon distinct from ''
Baryonyx walkeri ''Baryonyx'' () is a genus of theropod dinosaur which lived in the Barremian Geological stage, stage of the Early Cretaceous Period (geology), period, about 130–125 million years ago. The first skeleton was discovered in 1983 in the Smokejack ...
'' by Barker, Naish & Gostling (2023). * Barker ''et al.'' (2023) reconstruct the endocasts of the baryonychine spinosaurids ''Baryonyx walkeri'' and ''
Ceratosuchops inferodios ''Ceratosuchops'' (meaning "horned crocodile face") is a genus of spinosaurid from the Early Cretaceous (Barremian) of Britain. Discovery and naming The holotype remains of this taxon consist of IWCMS 2014.95.5 (premaxillary bodies), IWCM ...
'', finding their morphology to be similar to non-maniraptoriform theropods despite their highly modified skulls. * The first baryonychine teeth from South America reported to date are described from the Lower Cretaceous Feliz Deserto Formation (Brazil) by Lacerda ''et al.'' (2023). * Redescription of the anatomy of the skull of '' Irritator challengeri'' and a study on the affinities of this spinosaurid is published by Schade ''et al.'' (2023). *Description of a pathological tooth of ''
Spinosaurus ''Spinosaurus'' (; ) is a genus of large spinosaurid theropod dinosaurs that lived in what now is North Africa during the Cenomanian faunal stage, stage of the Late Cretaceous Period (geology), period, about 100 to 94 annum, million year ...
'' from the Late Cretaceous Ifezouane Formation (
Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...
) is published by Smith and Martill (2023), representing the first record of external dental pathology in a spinosaurine spinosaurid. * Reconstruction of the musculature of the pectoral girdle and forelimbs in
megaraptora Megaraptora is a clade of carnivorous theropod dinosaurs. Its derived members, the Megaraptoridae are noted for their large hand claws and powerfully-built forelimbs, which are usually reduced in size in other large theropods. Although undoubt ...
n theropods is presented by Aranciaga Rolando ''et al.'' (2023). * A pathological third
metatarsal The metatarsal bones or metatarsus (: metatarsi) are a group of five long bones in the midfoot, located between the tarsal bones (which form the heel and the ankle) and the phalanges ( toes). Lacking individual names, the metatarsal bones are ...
of ''
Phuwiangvenator ''Phuwiangvenator'' () is an extinct genus of megaraptoran Theropoda, theropod that lived during the Early Cretaceous period in what is now Thailand. It contains only the type species, ''P. yaemniyomi''. The genus, generic name of ''Phuwiangven ...
'', indicating that the bone experienced a
greenstick fracture A greenstick fracture is a partial bone break that typically occurs in children due to their more flexible and resilient bone composition. This fracture pattern is characterized by a break on one side of the bone while the other side remains inta ...
and healed before the animal's death, is described from the
Lower Cretaceous Lower may refer to: * ''Lower'' (album), 2025 album by Benjamin Booker * Lower (surname) * Lower Township, New Jersey *Lower Receiver (firearms) * Lower Wick Gloucestershire, England See also * Nizhny {{Disambiguation ...
Sao Khua Formation The Sao Khua Formation () is a middle member of the Khorat Group. It consists of an alteration of pale red to yellowish-gray, fine to medium-grained sandstone and grayish-reddish brown siltstone and clay. Rare pale red to light gray conglomerates ...
(
Khon Kaen Khon Kaen (, ) is the capital of Khon Kaen province and the List of municipalities in Thailand#Largest cities by urban population, fourth-largest city in Thailand. It is one of the four major cities of Isan, Northeast Thailand, also known as the ...
,
Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...
) by Samathi ''et al''. (2023). * A probable megaraptorid frontal and fused parietal fragment, representing the oldest megaraptorid skull element reported to date, is described from the
Aptian The Aptian is an age (geology), age in the geologic timescale or a stage (stratigraphy), stage in the stratigraphic column. It is a subdivision of the Early Cretaceous, Early or Lower Cretaceous epoch (geology), Epoch or series (stratigraphy), S ...
upper Strzelecki Group (the "Wonthaggi Formation";
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
) by Kotevski ''et al.'' (2023). * A study estimating the number of
telencephalic The cerebrum (: cerebra), telencephalon or endbrain is the largest part of the brain, containing the cerebral cortex (of the two cerebral hemispheres) as well as several subcortical structures, including the hippocampus, basal ganglia, and olfac ...
neuron A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural net ...
s in theropod dinosaurs is published by Herculano-Houzel (2023), who argues that ''
Allosaurus ''Allosaurus'' ( ) is an extinct genus of theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic period ( Kimmeridgian to late Tithonian ages). The first fossil remains that could definitively be ascribed to th ...
'' and ''
Tyrannosaurus ''Tyrannosaurus'' () is a genus of large theropod dinosaur. The type species ''Tyrannosaurus rex'' ( meaning 'king' in Latin), often shortened to ''T. rex'' or colloquially t-rex, is one of the best represented theropods. It lived througho ...
'' are endotherms with baboon- and monkey-like numbers of neurons; however, this study has been criticized. * The study suggesting that
carnosaur Carnosauria is an extinct group of carnivorous theropod dinosaurs that lived during the Jurassic and Cretaceous periods. While Carnosauria was historically considered largely synonymous with Allosauroidea, some recent studies have revived Carn ...
s like ''Allosaurus'' were primarily scavengers that fed on sauropod carcasses, originally published by Pahl and Ruedas (2021) is criticized by Kane ''et al.'' (2023) but later defended by Pahl and Ruehdas (2023). * Description of the endocranial anatomy of ''Allosaurus fragilis'' and ''A. jimmadseni'' is published by Lessner ''et al.'' (2023). * Yu ''et al.'' (2023) describe a probable
metriacanthosaurid Metriacanthosauridae (Greek for "moderately-spined lizards") is an extinct family of allosauroid theropod dinosaurs that lived in Europe and Asia from the Middle Jurassic to the Early Cretaceous. The family is split into two subgroups: Metriacant ...
tooth from the Middle Jurassic Dongdaqiao Formation (China), interpret its morphological similarities to velociraptorine teeth as most likely resulting from
convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last comm ...
, and argue that other Jurassic dromaeosaurid-like teeth from the Jurassic deposits of Asia and Europe might be teeth of non-dromaeosaurid theropods. * Carrano (2023) describes an incomplete theropod skeleton from the Lower Cretaceous Arundel Clay (
Maryland Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
), representing the first definitive record of ''
Acrocanthosaurus ''Acrocanthosaurus'' ( ; ) is a genus of carcharodontosaurid dinosaurs that existed in what is now North America during the Aptian and early Albian stages of the Early Cretaceous, from 113 to 110 million years ago. Like most dinosaur genera, ...
'' from the eastern part of North America reported to date. * Zhang ''et al.'' (2023) report the discovery of fossil downy feathers of coelurosaurs from the Lower Cretaceous Zhonggou Formation (China), with macromorphology (including rachis, barbs and barbules) essentially the same as in modern bird feathers, but with the microscopic morphology noticeably different from that of living bird feathers. * Johnson-Ransom ''et al.'' (2023) estimate bite force and cranial stresses in tyrannosauroid theropods, and interpret their findings as indicative of greater cranial stress and greater bite force in tyrannosaurids than in early-diverging tyrannosauroids. * Carr (2023) redescribes the hindlimb of the
lectotype In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to anchor or centralizes ...
of '' Alectrosaurus olseni'', describes a partial tyrannosauroid skull from the
Iren Dabasu Formation The Iren Dabasu Formation (also known as Erlian Formation) is a Late Cretaceous geologic Formation (geology), formation in the Erenhot, Iren Nor region of Inner Mongolia. Dinosaur remains diagnostic to the genus level are among the fossils that h ...
(China) with similarities to skulls of ''Raptorex kriegsteini'' and juvenile ''Tyrannosaurus rex'', and questions the assignment of fossil material from Mongolia and Uzbekistan to the genus ''Alectrosaurus''. * Yun (2023) describes a tyrannosaurid pedal ungual from the Williams Fork Formation of
Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...
(
USA The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguous ...
). * Therrien ''et al.'' (2023) describe a juvenile specimen of ''
Gorgosaurus libratus ''Gorgosaurus'' ( ; ) is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period (geology), Period (Campanian), between about 76.5 and 75 million years ago. Fossil remains have been ...
'' from the
Dinosaur Park Formation The Dinosaur Park Formation is the uppermost member of the Belly River Group (also known as the Judith River Group), a major geologic unit in southern Alberta. It was deposited during the Campanian stage of the Late Cretaceous, between about 7 ...
(Alberta, Canada), preserved with remains of two specimens of '' Citipes elegans'' within their first year of life in its abdominal cavity, and interpret this finding as indicating that ''G. libratus'' underwent a dietary shift over the course of its life. * New fossil material of ''
Albertosaurus sarcophagus ''Albertosaurus'' (; meaning "Alberta lizard") is a genus of large tyrannosaurid theropod dinosaur that lived in northwestern North America during the early to middle Maastrichtian age of the Late Cretaceous period, about 71 million yea ...
'', including the left pubis with tooth traces interpreted as evidence of cannibalism, is described from the Danek Bonebed (
Horseshoe Canyon Formation The Horseshoe Canyon Formation is a stratigraphic unit of the Western Canada Sedimentary Basin in southwestern Alberta. It takes its name from Horseshoe Canyon, an area of badlands near Drumheller. The Horseshoe Canyon Formation is part of th ...
; Alberta, Canada) by Coppock &
Currie Currie is a village and suburb on the outskirts of Edinburgh, Scotland, situated south west of the city centre. Formerly within the County of Midlothian, it now falls within the jurisdiction of the City of Edinburgh Council. It is situated be ...
(2023). * A study on the affinities of tyrannosaurines, reanalyzing the dataset of Warshaw & Fowler (2022), is published by Scherer & Voiculescu-Holvad (2023), who name a new clade Teratophoneini, and find no support for a single
anagenetic Anagenesis is the gradual evolution of a species that continues to exist as an interbreeding population. This contrasts with cladogenesis, which occurs when branching or splitting occurs, leading to two or more lineages and resulting in separate ...
lineage within derived tyrannosaurines; their findings are subsequently contested by Warshaw, Barrera Guevara & Fowler (2024), whose phylogenetic analysis indicates that recognized ''Daspletosaurus'' species represent a single anagenetic lineage ancestral to ''Tyrannosaurus''-line tyrannosaurines. * Fiorillo ''et al.'' (2023) report the discovery of a theropod track from the Chignik Formation (
Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
) produced by a tyrannosaur larger than ''
Nanuqsaurus hoglundi ''Nanuqsaurus'' (meaning "polar bear lizard") is a genus of tyrannosaurine theropod dinosaur known from the Late Cretaceous period (middle Maastrichtian age) Prince Creek Formation of the North Slope of Alaska, having lived roughly 70-68 millio ...
'', and interpret this finding as suggestive of different selective pressures on tyrannosaurids between the northern and southern extremes of Alaska. * Hodnett ''et al.'' (2023) report on a tyrannosaur tooth (assigned to ''cf. Tyrannosaurus sp.'') from the
Harebell Formation The Harebell Formation is a Late Cretaceous (Maastrichtian) geologic formation in Wyoming which outcrops in parts of the Yellowstone National Park. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered fro ...
(
Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...
, United States), marking the first confirmed record of a dinosaur fossil discovered within the
Yellowstone National Park Yellowstone National Park is a List of national parks of the United States, national park of the United States located in the northwest corner of Wyoming, with small portions extending into Montana and Idaho. It was established by the 42nd U ...
. * Evidence of preservation of elements associated with bone remodeling and redeposition (sulfur, calcium, zinc) in a specimen of ''Tyrannosaurus rex'', interpreted as indicative of preservation of original endogenous chemistry in the studied specimen, is presented by Anné ''et al.'' (2023). * A study on the formation and function of the enlarged
ungual An ungual (from Latin ''unguis'', i.e. ''nail'') is a highly modified distal toe bone which ends in a hoof, claw, or nail. Elephants and ungulates have ungual phalanges, as did the sauropod Sauropoda (), whose members are known as sauropods (; ...
s of alvarezsauroid and therizinosaur theropods is published by Qin ''et al.'' (2023), who interpret their findings as indicative of the evolution of digging adaptions in late-diverging alvarezsauroids, find the unguals of early-branching therizinosaurs to perform well in piercing and pulling, and interpret the enlarged unguals of ''
Therizinosaurus ''Therizinosaurus'' (; meaning 'scythe lizard') is a genus of very large therizinosaurid dinosaurs that lived in Asia during the Late Cretaceous period in what is now the Nemegt Formation around 70 million years ago. It contains a single speci ...
'' as not adapted to functions that required considerable stress-bearing. * A study on the hindlimb variation between the best-preserved specimens of putative ornithomimosaurs from the
Angeac-Charente bonebed The Angeac-Charente bonebed is a fossil deposit located near Angeac-Charente in western France. It dates to the Berriasian stage of the Early Cretaceous, and is coeval with the Purbeck Group of Southern England. It has amongst the most diverse asse ...
(
France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
) is published by Pintore ''et al.'' (2023), who interpret their findings as indicative of the presence of sexual dimorphism in the studied theropods. * Two ornithomimid pedal
phalanges The phalanges (: phalanx ) are digit (anatomy), digital bones in the hands and foot, feet of most vertebrates. In primates, the Thumb, thumbs and Hallux, big toes have two phalanges while the other Digit (anatomy), digits have three phalanges. ...
are described from the Late Cretaceous
Fox Hills Formation The Fox Hills Formation is a Cretaceous geologic formation in the northwestern Great Plains of North America. It is present from Alberta on the north to Colorado in the south. Fossil remains of dinosaurs, including tyrannosaurs, as well as lar ...
(
South Dakota South Dakota (; Sioux language, Sioux: , ) is a U.S. state, state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Dakota people, Dakota Sioux ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
) by Chamberlain, Knoll, and Sertich (2023), representing the first dinosaur skeletal material from the formation. * Averianov ''et al.'' (2023) describe an ornithomimid tibia from the Maastrichtian Udurchukan Formation, (
Amur Oblast Amur Oblast () is a federal subject of Russia (an oblast), located on the banks of the Amur and Zeya rivers in the Russian Far East. The oblast borders Heilongjiang province of the People's Republic of China (PRC) to the south. The administrati ...
,
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
), representing the first finding of an ornithomimid in the Upper Cretaceous strata from the Russian Far East reported to date. * A study on the bone histology of the holotype specimen of '' Parvicursor remotus'' is published by Averianov ''et al.'' (2023), who interpret this specimen as a young individual, not more than one year old, and reevaluate the course of alvarezsaurid miniaturization inferred by Qin ''et al.'' (2021), finding no compelling morphological data indicating that
parvicursorine Alvarezsauridae is a family of small, long-legged dinosaurs. Although originally thought to represent the earliest known flightless birds, they are now thought to be an early diverging branch of maniraptoran theropods. Alvarezsaurids were highly ...
alvarezsaurids fed on colonies of social insects and that their miniaturization was related to myrmecophagy. * A study on the range of motion at the shoulder in '' Mononykus olecranus'' is published by Senter (2023). * Wills, Underwood & Barrett (2023) identify therizinosauroid and troodontid teeth, as well as three morphotypes of dromaeosaurid teeth, in a sample of isolated theropod teeth from the Middle Jurassic (
Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...
) microvertebrate sites in the
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
. * Reconstruction of the hindlimb musculature of '' Falcarius utahensis'' is presented by Smith (2023). * Smith & Gillette (2023) reconstruct soft tissues of the hindlimbs and likely posture of '' Nothronychus graffami''. * Skeletal indicators of a
propatagium The patagium (: patagia) is a membranous body part that assists an animal in obtaining lift when gliding or flying. The structure is found in extant and extinct groups of flying and gliding animals including bats, theropod dinosaurs (including bi ...
are investigated by Uno & Hirasawa (2023), supporting the presence of this structure in non-avian pennaraptorans such as ''
Caudipteryx ''Caudipteryx'' (meaning "tail feather") is a genus of small oviraptorosaur dinosaurs that lived in Asia during the Early Cretaceous, around 124.6 million years ago. They were feathered and extremely birdlike in their overall appearance, to the ...
'' and ''
Microraptor ''Microraptor'' (Greek language, Greek, μικρός, ''mīkros'': "small"; Latin language, Latin, ''raptor'': "one who seizes") is a genus of small, four-winged dromaeosaurid dinosaurs. Numerous well-preserved fossil specimens have been recovere ...
''. * A review of the evidence for partially buried eggs and their significance for the evolution of contact incubation in Mesozoic pennaraptorans is published by Hogan & Varrcchio (2023). * Averianov & Lopatin (2023) describe fossil material (metatarsals) of a caenagnathid with similaries to '' Elmisaurus rarus'' and a dromaeosaurid with similarities to ''
Velociraptor mongoliensis ''Velociraptor'' (; ) is a genus of small dromaeosaurid dinosaurs that lived in Asia during the Late Cretaceous epoch, about 75 million to 71 million years ago. Two species are currently recognized, although others have been assigned in the ...
'' from the Upper Cretaceous
Bostobe Formation The Bostobe Formation () is a geological formation in Qaraghandy & Qyzylorda, Kazakhastan whose strata date back to the Late Cretaceous (Santonian to early Campanian stages, approximately 85 Ma). The sandstones and claystones of the formation ...
(
Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a landlocked country primarily in Central Asia, with a European Kazakhstan, small portion in Eastern Europe. It borders Russia to the Kazakhstan–Russia border, north and west, China to th ...
). * Voris, Zelenitsky & Therrien (2023) describe new caenagnathid fossil material from the upper Maastrichtian portion of the
Scollard Formation The Scollard Formation is an Upper Cretaceous to lower Palaeocene stratigraphic unit of the Western Canada Sedimentary Basin in southwestern Alberta. Its deposition spanned the time interval from latest Cretaceous to early Paleocene, and it inc ...
(
Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...
,
Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
), including fossils indicative of the presence of a large-bodied taxon similar to ''
Anzu wyliei ''Anzu'' (named for Anzû (mythology), Anzû, a bird-like Daemon (classical mythology), daemon in Ancient Mesopotamian religion) is a monospecific genus of caenagnathidae, caenagnathid dinosaur from North Dakota, South Dakota and Montana that liv ...
'' or ''
Caenagnathus collinsi ''Caenagnathus'' ('recent jaw') is a genus of caenagnathid oviraptorosaurian dinosaur from the late Cretaceous period (Campanian stage; ~75 million years ago). It is known from partial remains including lower jaws, a tail vertebra, hand bones, ...
''. * The most complete caenagnathid specimens from the southern part of North America reported to date are described from the Campanian
Aguja Formation The Aguja Formation is a geological formation in North America, exposed in Texas, United States and Chihuahua and Coahuila in Mexico, whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered ...
(
Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
) by Wick, Lehman & Fortner (2023), who present a histology-based growth model for one of the studied specimens (the first for a caenagnathid), indicating that it needed least five years to approach fully adult size. * The feasibility of contact incubation by
oviraptorid Oviraptoridae is a group of bird-like, herbivorous and omnivorous maniraptoran dinosaurs. Oviraptorids are characterized by their toothless, parrot-like beaks and, in some cases, elaborate crests. They were generally small, measuring between one ...
s based on their nest architecture is experimentally tested by Hogan (2023). * A review of bone microstructure and
histology Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissue (biology), tissues. Histology is the microscopic counterpart to gross anatomy, which looks at large ...
in
dromaeosaurids Dromaeosauridae () is a family of feathered coelurosaurian theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Gree ...
and
troodontids Troodontidae is a clade of bird-like theropod dinosaurs from the Late Jurassic to Late Cretaceous. During most of the 20th century, troodontid fossils were few and incomplete and they have therefore been allied, at various times, with many dinos ...
is published by Martin, Currie & Kundrát (2023). * Yang ''et al.'' (2023) report the first discovery of fossil materials of a large-bodied dromaeosaurid (probably a eudromaeosaur) from the Upper Cretaceous Quantou Formation (Jilin, China). * Croudace ''et al.'' (2023) reconstruct the feather colouration of an approximately one-year-old individual of '' Wulong bohaiensis'', reporting evidence indicative of the presence of iridescent plumage of the forelimb and hindlimb remiges and grey plumage on other portions of the body. * A partial left tibia and
articulated An articulated vehicle is a vehicle which has a permanent or semi-permanent coupling in its construction. This coupling works as a large pivot joint, allowing it to bend and turn more sharply. There are many kinds, from heavy equipment to buse ...
proximal tarsals, likely belonging to an indeterminate velociraptorine, are described from the
Upper Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cret ...
Lo Hueco fossil site (
Cuenca Cuenca may refer to: People * Cuenca (surname) Places Ecuador * Cuenca Canton, in the Azuay Province ** Cuenca, Ecuador, capital of Cuenca Canton and Azuay Province ** Roman Catholic Archdiocese of Cuenca Peru * Cuenca District, Huarochirí ...
,
Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
) by Malafaia ''et al''. (2023), who also review the European theropods of the Late Cretaceous. * Averianov & Lopatin (2023) describe new fossil material of '' Kansaignathus sogdianus'' from the Santonian Ialovachsk Formation (
Tajikistan Tajikistan, officially the Republic of Tajikistan, is a landlocked country in Central Asia. Dushanbe is the capital city, capital and most populous city. Tajikistan borders Afghanistan to the Afghanistan–Tajikistan border, south, Uzbekistan to ...
), and confirm the phylogenetic placement of ''K. sogdianus'' as the
basalmost In phylogenetics, basal is the direction of the ''base'' (or root) of a rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to th ...
Asiatic velociraptorine. * Czepiński (2023) describes a specimen of ''
Shri devi ''Shri'' (named after Palden Lhamo, a Buddhist deity) is an extinct genus of small dromaeosaurid dinosaurs that lived in what is now Mongolia during the Late Cretaceous. The genus contains two species; the first, ''Shri devi'', was described in ...
'' with a partial skull from the Upper Cretaceous
Barun Goyot Formation The Baruungoyot Formation (also known as Barun Goyot) is a geological formation dating to the Late Cretaceous Period. It is located within and is widely represented in the Gobi Desert Basin, in the Ömnögovi Province of Mongolia. Descriptio ...
(
Mongolia Mongolia is a landlocked country in East Asia, bordered by Russia to the north and China to the south and southeast. It covers an area of , with a population of 3.5 million, making it the world's List of countries and dependencies by po ...
), and reports that the anatomy of the skull confirms close affinities of ''Shri'' with ''Velociraptor mongoliensis'', but also that the skull has anatomical features suggesting
convergence Convergence may refer to: Arts and media Literature *''Convergence'' (book series), edited by Ruth Nanda Anshen *Convergence (comics), "Convergence" (comics), two separate story lines published by DC Comics: **A four-part crossover storyline that ...
to the North American
eudromaeosauria Eudromaeosauria (International Phonetic Alphabet, ; "true dromaeosaurs") is a subgroup of terrestrial Dromaeosauridae, dromaeosaurid theropod dinosaurs. They were small to large-sized predators that flourished during the Cretaceous Period (geolo ...
ns. * A study on the nasal structures of ''Velociraptor mongoliensis'', indicating that this theropod was unlikely to have a fully developed nasal thermoregulation apparatus for its brain as seen in modern birds, is published by Tada ''et al.'' (2023). * A study on the bone histology of the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
of '' Liaoningvenator curriei'' is published by Martin, Caizhi & Kundrát (2023), who interpret their findings as indicative of a growth pattern transitive between those of
basalmost In phylogenetics, basal is the direction of the ''base'' (or root) of a rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to th ...
and more derived
troodontids Troodontidae is a clade of bird-like theropod dinosaurs from the Late Jurassic to Late Cretaceous. During most of the 20th century, troodontid fossils were few and incomplete and they have therefore been allied, at various times, with many dinos ...
. * Evidence from eggshells of ''
Troodon ''Troodon'' ( ; ''Troödon'' in older sources) is a controversial genus of relatively small, bird-like theropod dinosaurs definitively known from the Campanian age of the Late Cretaceous period (about 77 million years ago). It includes at l ...
'', interpreted as indicative of endothermic physiology but also of reptile-like eggshell mineralization process, is presented by Tagliavento ''et al.'' (2023).


Sauropodomorph research

* Lockley ''et al.'' (2023) evaluate a number of trackways assigned to basal saurischians, including those belonging to the ichnogenera ''
Otozoum ''Otozoum'' ("giant animal") is an extinct ichnogenus (fossilized footprints and other markings) of sauropodomorph dinosaur from the Late Triassic-Middle Jurassic sandstones. Footprints were made by heavy, bipedal or, sometimes, quadrupedal anima ...
'', '' Pseudotetrasauropus'', '' Evazoum'', and '' Kalosauropus'', and examine their implications on the gait of "
prosauropod Sauropodomorpha ( ; from Greek, meaning "lizard-footed forms") is an extinct clade of long-necked, herbivorous, saurischian dinosaurs that includes the Sauropoda, sauropods and their ancestral relatives. Sauropods generally grew to very large siz ...
s". * A new specimen of '' Buriolestes schultzi'', interpreted as stouter than other specimens of ''B. schultzi'' and providing evidence of previously unknown variation in robustness within this species, is described from the Late Triassic of southern
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
by Moro ''et al.'' (2023). * A study on sauropodomorph tracks from the Upper Triassic lower Elliot Formation (
Lesotho Lesotho, formally the Kingdom of Lesotho and formerly known as Basutoland, is a landlocked country in Southern Africa. Entirely surrounded by South Africa, it is the largest of only three sovereign enclave and exclave, enclaves in the world, t ...
) is published by Sciscio ''et al.'' (2023), who interpret the studied tracks as confirming that sauropodomorphs already evolved large body size by the
Norian The Norian is a division of the Triassic geological period, Period. It has the rank of an age (geology), age (geochronology) or stage (stratigraphy), stage (chronostratigraphy). It lasted from ~227.3 to Mya (unit), million years ago. It was prec ...
, but also indicating that the makers of the studied tracks used both bipedal and quadrupedal locomotion styles during a 10-million-years interval in the Norian. * Chapelle, Botha & Choiniere (2023) study the histology of a small sauropodomorph humerus from the upper Elliot Formation (
South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...
), and interpret this specimen as a bone of a skeletally mature individual of a new taxon with a body mass of approximately 75.35 kg, representing the smallest known Jurassic sauropodomorph reported to date. * New information on the anatomy of '' Jaklapallisaurus asymmetricus'' is presented by
Ezcurra Ezcurra is a surname. Notable people with the surname include: * Alma Ezcurra (born 1986), Spanish politician * Bautista Ezcurra (born 1995), Argentine rugby union player * Encarnación Ezcurra (1795–1838), Argentine political activist * Exequiel ...
''et al.'' (2023), who interpret ''J. asymmetricus'' as a member of
Unaysauridae Unaysauridae is a clade of basal sauropodomorphs from the Late Triassic of India and Brazil. Diagnosis and systematics Unaysauridae was defined by Müller ''et al.'' (2018) as the most inclusive clade including ''Unaysaurus tolentinoi'', but no ...
. * Müller ''et al''. (2023) describe the remains of a juvenile specimen of ''
Unaysaurus ''Unaysaurus'' is a genus of unaysauridae, unaysaurid sauropodomorpha, sauropodomorph herbivore dinosaur. Discovered in southern Brazil, in the geopark of Paleorrota, in 1998, and announced in a press conference on Thursday, December 3, 2004, it ...
'', found associated with the holotype, from the Late Triassic
Caturrita Formation The Caturrita Formation is a rock formation found in Rio Grande do Sul, Brazil. Its sediments were deposited in the Paraná Basin. The formation is from the Upper Triassic and forms part of the Santa Maria Supersequence in the upper section of th ...
(
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
). * Taxonomic revision of basal sauropodomorph specimens stored in the Palaeontological Collection of Tübingen, historically referred to the genus ''
Plateosaurus ''Plateosaurus'' (probably meaning "broad lizard", often mistranslated as "flat lizard") is a genus of plateosaurid dinosaur that lived during the Late Triassic period, around 214 to 204 million years ago, in what is now Central and Northern Eu ...
'', is published by Regalado Fernandez ''et al.'' (2023). * Aureliano ''et al.'' (2023) provide evidence of the presence of an invasive air sac system in '' Macrocollum itaquii''. * Bem & Müller (2023) report the first discovery of the fossil material of ''Macrocollum itaquii'' outside its type locality. * Moopen ''et al.'' (2023) describe material of a probable lessemsaurid from the Triassic lower Elliot Formation and estimating it to be one of the largest sauropodomorphs from the Norian of
South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...
, as well as the first plant-vertebrate fossil associations in the formation. * A study on the evolution of sauropod body mass is published by D'Emic (2023), who finds that sauropods independently surpassed the maximum body mass of terrestrial mammals at least three dozen times in their evolutionary history. * Description of the anatomy of a partial juvenile sauropod vertebral series from the Middle Jurassic Nam Phong Formation (
Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...
), interpreted as indicative of non-
eusauropod Eusauropoda (meaning "True Lizard Foot") is a derived clade of sauropod dinosaurs. Eusauropods represent the node-based group that includes all descendant sauropods starting with the basal eusauropods of ''Shunosaurus'', and possibly ''Barapasaur ...
affinities of the studied specimen, is published by Hanta ''et al.'' (2023). *Description of new eusauropod fossil material from the Middle Jurassic Dongdaqiao Formation (
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
) is published by Wei ''et al''. (2023), who interpret these findings as showing that gigantic sauropods were more widespread than previously known during the Middle Jurassic. * A juvenile sauropod specimen, most closely resembling early-diverging eusauropods from the Middle Jurassic but sharing some derived features with the Late Jurassic mamenchisaurids and neosauropods, is described from the Middle Jurassic Dongdaqiao Formation (East Tibet, China) by An ''et al.'' (2023). * The holotype of ''
Mamenchisaurus sinocanadorum ''Mamenchisaurus'' ( , or spelling pronunciation ) is an extinct genus of sauropod dinosaurs known for their remarkably long necks which made up nearly half the total body length. Numerous species have been assigned to the genus; however, the val ...
'' is redescribed by Moore ''et al.'' (2023), who also interpret ''
Bellusaurus ''Bellusaurus'' (meaning "Beautiful lizard", from Vulgar Latin ''bellus'' 'beautiful' (masculine form) and Ancient Greek ''sauros'' 'lizard') was a sauropod dinosaur from the Late Jurassic ( Oxfordian) known from juvenile specimens that would hav ...
'' and '' Daanosaurus'' as juvenile
mamenchisaurids Mamenchisauridae is a family of sauropod dinosaurs belonging to the Eusauropoda known from the Jurassic and Early Cretaceous of Asia and Africa. Mamenchisaurids are characterized by their proportionately extremely long necks. Some members of the ...
. * A tooth of a possible member of
Turiasauria Turiasauria is an unranked clade of eusauropod dinosaurs known from Middle Jurassic to Early Cretaceous deposits in Europe, North America, and Africa. Description Turiasauria was originally erected by Royo-Torres et al. (2006) to include '' Tur ...
, which might represent the oldest record of the group reported to date, is described from the Lower Jurassic (
Pliensbachian The Pliensbachian is an age of the geologic timescale and stage in the stratigraphic column. It is part of the Early or Lower Jurassic Epoch or Series and spans the time between 192.9 ±0.3 Ma and 184.2 ±0.3 Ma (million years ago). The Plie ...
) Halse Formation (
Denmark Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous a ...
) by Milàn & Mateus (2023). * A study on the anatomy of the skull of '' Bajadasaurus pronuspinax'' is published by Garderes ''et al.'' (2023). * A study on bifurcated cervical ribs in apatosaurines is published by
Wedel Wedel () is a town in the Pinneberg (district), district of Pinneberg, in Schleswig-Holstein, in northern Germany. It is situated on the right bank of the Elbe, approximately south of Elmshorn, and west of Hamburg. History Foundation and Mi ...
&
Taylor Taylor, Taylors or Taylor's may refer to: People * Taylor (surname) ** List of people with surname Taylor * Taylor (given name), including Tayla and Taylah * Taylor sept, a branch of Scottish clan Cameron * Justice Taylor (disambiguation) ...
(2023), who interpret the studied structures as divergent muscle attachments, likely enabling improved muscular control in the middle of the neck. * A rebbachisaurid vertebra from the
La Amarga Formation The La Amarga Formation is a geologic formation with outcrops in the Argentine provinces of Río Negro, Neuquén, and Mendoza. It is the oldest Cretaceous terrestrial formation in the Neuquén Basin. The type locality is La Amarga Arroyo and ...
(
Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
) is redescribed by Lerzo (2023), who finds it to be a derived member of Rebbachisaurinae. * A study on the microanatomy of the long bones of '' Nigersaurus taqueti'' is published by Lefebvre, Allain & Houssaye (2023), who interpret their findings as indicating that microanatomical structure in sauropod limb bones was not subject to drastic selective pressures imposed by heavy weight-bearing. * New rebbachisaurid specimen, providing new information on the anatomy of the hindlimbs of rebbachisaurids, is described from the Cenomanian
Huincul Formation The Huincul Formation is a geologic formation of Late Cretaceous (Cenomanian to Turonian, Early Turonian) age of the Neuquén Basin that outcrops in the Mendoza Province, Mendoza, Rio Negro Province, Río Negro and Neuquén Provinces of northern ...
(Argentina) by Bellardini ''et al.'' (2023). * Torcida Fernández-Baldor ''et al.'' (2023) describe a dentary and several teeth of a basal
macronaria Macronaria is a clade of sauropod dinosaurs. Macronarians are named after the large diameter of the nasal opening of their skull, known as the external naris, which exceeded the size of the orbit, the skull opening where the eye is located (hence ...
n close to ''
Camarasaurus ''Camarasaurus'' ( ) is a genus of sauropod dinosaur that lived in North America during the Late Jurassic period. Its fossil remains have been found in the Morrison Formation, dating to the Kimmeridgian and Tithonian ages of the Jurassic, betwe ...
'' from the Valdepalazuelos site ( Rupelo Formation;
Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
) living during the
Tithonian In the geological timescale, the Tithonian is the latest age (geology), age of the Late Jurassic Epoch and the uppermost stage (stratigraphy), stage of the Upper Jurassic Series. It spans the time between 149.2 ±0.7 annum, Ma and 143.1 ±0.6 (mi ...
Berriasian In the geological timescale, the Berriasian is an age/ stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 143.1 ±0.6 Ma and 137.05 ± 0.2 (million years ago) ...
transition, providing evidence of the presence of two macronarian taxa at the Valdepalazuelos site. * Cervical vertebra representing the first record of a
titanosauriform Macronaria is a clade of sauropod dinosaurs. Macronarians are named after the large diameter of the nasal opening of their skull, known as the external naris, which exceeded the size of the orbit, the skull opening where the eye is located (hence ...
sauropod from the Lower Cretaceous Kanmon Group (
Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
) is described by Tatehata, Mukunoki & Tanoue (2023). * Sauropod fossil material, including a vertebra of a possible member of the genus ''
Ornithopsis ''Ornithopsis'' (meaning "bird-likeness") is a genus of sauropod dinosaur, from the Early Cretaceous of England and possibly Germany. The type species, which is the only species seen as valid today, is ''O. hulkei,'' which is only known from frag ...
'', is described from the Lower Cretaceous sediments from the Balve II locality (
Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...
) by Hornung, Sachs & Schwermann (2023), representing the first finding of sauropod fossils from the upland environment in Europe reported to date. * New information on the
pneumatization Skeletal pneumaticity is the presence of air spaces within bones. It is generally produced during development by excavation of bone by pneumatic diverticula (air sacs) from an air-filled space, such as the lungs or nasal cavity. Pneumatization is h ...
of the ribs of the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
specimen of '' Brachiosaurus altithorax'' is presented by Taylor & Wedel (2023). * Lim ''et al.'' (2023) report the discovery of a fibula of a member of the family
Euhelopodidae Euhelopodidae is a family of sauropod dinosaurs of disputed membership and affinities, which contains '' Euhelopus'' and its close relatives. Most proposed euhelopodids are from East Asia. Euhelopodidae was first recognized by Carl Wiman in 1929 ...
from the strata of the Lower Cretaceous Grès supérieurs Formation at Koh Paur island, representing the first finding of a non-avian dinosaur from
Cambodia Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...
reported to date. * Cruzado-Caballero ''et al.'' (2023) describe two new cases of caudal pathology in titanosaurs from the Late Cretaceous of Argentina and evaluate these cases for interpreting the commonness of pathology occurring in the fossil record. * The pneumaticity of a titanosaur specimen from the Black Peaks Formation (
Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
) is investigated by Fronimos (2023). * Averianov ''et al.'' (2023) describe a series of caudal vertebrae representing the first sauropod material from the Shestakovo 3 locality from the Lower Cretaceous
Ilek Formation The Ilek Formation is a Lower Cretaceous geologic Formation (geology), formation in Western Siberia. Many different fossils have been recovered from the formation. It overlies the Late Jurassic Tyazhin Formation and underlies the Albian Kiya Form ...
(
Kemerovo Oblast Kemerovo Oblast (, ), also known as Kuzbass (, ), after the Kuznetsk Basin, is a federal subjects of Russia, federal subject of Russia (an oblast). Kemerovo is the administrative center and largest city of the oblast. Kemerovo Oblast is one of Rus ...
,
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
), and interpret it as new fossil material of ''
Sibirotitan astrosacralis ''Sibirotitan'' ("Siberian Titan (mythology), titan") is a genus of somphospondyli, somphospondyl sauropod from the Ilek Formation of Russia. The type species, type and only species is ''S. astrosacralis''. Discovery and naming The material as ...
''. * New specimen of '' Diamantinasaurus matildae'', including the skull preserving cranial elements not previously known for this taxon and showing similarities with the skull of '' Sarmientosaurus musacchioi'', is described from the Upper Cretaceous
Winton Formation The Winton Formation is a Cretaceous Formation (geology), geological formation in central-western Queensland, Australia. It is late Albian to early Turonian in age. The formation blankets large areas of central-western Queensland. It consists of ...
(
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
) by Poropat ''et al.'' (2023). * Titanosaur teeth representing three distinct
morphotype In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative ''phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the s ...
s, including the largest titanosaur tooth ever found, are described from the Upper Cretaceous
Serra da Galga Formation The Serra da Galga Formation is a geological formation in Minas Gerais state of southeastern Brazil. Its strata date back to the Maastrichtian, and are part of the Bauru Group. It was originally considered a member of the Marília Formation. Di ...
(
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
) by Silva Junior ''et al.'' (2023). * Dhiman ''et al.'' (2023) report the discovery of 92 titanosaur egg clutches from the Upper Cretaceous
Lameta Formation The Lameta Formation, also known as the Infratrappean Beds (not to be confused with the contemporaneous Intertrappean Beds), is a sedimentary geological formation found in Madhya Pradesh, Gujarat, Maharashtra, Telangana, and Andhra Pradesh, Indi ...
(
Madhya Pradesh Madhya Pradesh (; ; ) is a state in central India. Its capital is Bhopal and the largest city is Indore, Indore. Other major cities includes Gwalior, Jabalpur, and Sagar, Madhya Pradesh, Sagar. Madhya Pradesh is the List of states and union te ...
,
India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
), including three types of clutches and assigned to six oospecies, interpret their findings as suggestive of higher diversity of titanosaur taxa from the Lameta Formation than indicated by body fossils, and evaluate the implications of the studied egg clutches for the knowledge of the reproductive biology of titanosaurs. * A study on the bone histology of '' Uberabatitan ribeiroi'', providing evidence of rapid, uninterrupted growth that ceased with the appearance of periodic interruptions in the advanced stages of development, is published by Windholz ''et al.'' (2023). * A study on the long bone histology of '' Muyelensaurus pecheni'' and '' Rinconsaurus caudamirus'' is published by González ''et al.'' (2023), who find no evidence of a correlation between the ontogenetic stage and the body size in both taxa, unlike in other neosauropods. * A new sauropod specimen (a saltasaurid
humerus The humerus (; : humeri) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius (bone), radius and ulna, and consists of three sections. The humeral upper extrem ...
) is described from the
Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...
deposits from the
Quseir Formation The Quseir Formation is a geological formation in the vicinity of the Kharga Oasis in Egypt.
(
Egypt Egypt ( , ), officially the Arab Republic of Egypt, is a country spanning the Northeast Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via the Sinai Peninsula. It is bordered by the Mediterranean Sea to northe ...
) by Wahba ''et al.'' (2023). * A sauropod tooth assigned to the family Opisthocoelicaudiidae, representing the first record of a sauropod from Late Cretaceous Russia, is described from the Udurchukan Formation, (
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
) by Averianov, Bolotsky, and Bolotsky (2023). *
Paul Paul may refer to: People * Paul (given name), a given name, including a list of people * Paul (surname), a list of people * Paul the Apostle, an apostle who wrote many of the books of the New Testament * Ray Hildebrand, half of the singing duo ...
and Larramendi (2023) suggest that some sauropods reached sizes comparable to the largest whales, and propose that the fragmentary taxon ''
Bruhathkayosaurus ''Bruhathkayosaurus'' (; meaning "huge-bodied lizard") is a genus of sauropod dinosaur found in the Kallamedu Formation of India. The fragmentary remains were originally described as a theropod, but it was later determined to be a titanosau ...
'' may have weighed between 110 and 170 tonnes. * Multiple sauropod tracks assigned to
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
''
Brontopodus ''Brontopodus'' is an ichnogenus of dinosaur footprint by sauropod trackmaker. This ichnogenus is mainly characterized by a wide-gauge trackway, which is distinguishable from narrow-gauge sauropod tracks like '' Breviparopus'' or '' Parabrontopod ...
'' isp., providing the first ichnological evidence of gregarious behavior in Cretaceous sauropods in Africa, are described from the Lower Formation of the
Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...
Djoua series in the In Amenas region of
Algeria Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Alger ...
by Zaagane ''et al.'' (2023).


Ornithischian research

* A study on the biomechanical properties of the skulls of '' Heterodontosaurus tucki'', '' Lesothosaurus diagnosticus'', '' Scelidosaurus harrisonii'', ''
Hypsilophodon foxii ''Hypsilophodon'' (; meaning "high-crested tooth") is a neornithischian dinosaur genus from the Early Cretaceous Period (geology), period of England. It has traditionally been considered an early member of the group Ornithopoda, but recent resear ...
'' and '' Psittacosaurus lujiatunensis'' is published by Button ''et al.'' (2023), who interpret their findings as indicative of limited functional convergence among studied taxa, which achieved comparable performance of the feeding apparatus through different adaptations. * A study on the evolution of forelimb muscle mechanics and function in ornithischian dinosaurs is published by Dempsey ''et al.'' (2023), who interpret their findings as indicating that thyreophorans, ornithopods and ceratopsians evolved quadrupedality through different patterns of rearrangement of forelimb musculature. * Review of the fossil record of ornithischian dinosaurs from Southeast Asia and southern China is published by Manitkoon ''et al.'' (2023) * Surmik ''et al.'' (2023) study ossified tendons of specimens of ''
Pinacosaurus ''Pinacosaurus'' (meaning "Plank lizard") is a genus of ankylosaurid thyreophoran dinosaur that lived in Asia during the Late Cretaceous (Campanian, roughly 75 to 71 million years ago), mainly in Mongolia and China. The first remains of the genu ...
grangeri'', ''
Edmontosaurus ''Edmontosaurus'' ( ) (meaning "lizard from Edmonton"), with the second species often colloquially and historically known as ''Anatosaurus'' or ''Anatotitan'' (meaning "duck lizard" and "giant duck"), is a genus of hadrosaurid (duck-billed) din ...
regalis''/"'' Ugrunaaluk kuukpikensis''" and ''
Homalocephale ''Homalocephale'' (from Greek ὁμαλός, ''homalos'', "even", and κεφαλή, ''kephalē'', "head") is a genus of pachycephalosaurid dinosaur that lived during the Late Cretaceous period of what is now the Nemegt Formation, Mongolia, about ...
calathocercos'', reporting the presence of collagenous fibre bundles and likely fibril bundles, blood vessels and associated cells in some of the studied samples, and argue that ossified tendons can be a source of molecular preservation in dinosaurs. * A study on the histology and enamel microstructure of the maxillary cheek teeth of ''Heterodontosaurus tucki'', providing the earliest known evidence of the presence of wear-resistant modified dentine in an ornithischian, is published by Calvert ''et al.'' (2023). * Description of the skull osteology of '' Manidens condorensis'' is published by Becerra ''et al.'' (2023). * Button & Zanno (2023) present a three-dimensional endocranial reconstruction of a specimen of ''
Thescelosaurus neglectus ''Thescelosaurus'' ( ) is a genus of ornithischian dinosaur that lived during the Late Cretaceous period in western North America. It was named and described in 1913 by the paleontologist Charles W. Gilmore; the type species is ''T. neglectus''. ...
'', and report the presence of brain traits interpreted as suggestive of cognitive and behavioral capabilities within the range of extant reptiles, as well as a narrow hearing range, acute olfaction and
vestibular The Vestibular (from , "entrance hall") is a competitive examination and is the primary and widespread entrance system used by Brazilian universities to select the students admitted. The Vestibular usually takes place from November to January, ...
sensitivity which might represent adaptations for burrowing behaviors.


Thyreophoran research

* A study on the phylogenetic relationships of thyreophorans is published by Raven ''et al.'' (2023), who identify four distinct ankylosaur clades, with the long-standing clade Nodosauridae recovered as
paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...
; they suggest replacing the latter with the names
Panoplosauridae Nodosauridae is a family of ankylosaurian dinosaurs known from the Late Jurassic to the Late Cretaceous periods in what is now Asia, Europe, North America, and possibly South America. While traditionally regarded as a monophyletic clade as the s ...
, Polacanthidae, and
Struthiosauridae Nodosauridae is a family of ankylosaurian dinosaurs known from the Late Jurassic to the Late Cretaceous periods in what is now Asia, Europe, North America, and possibly South America. While traditionally regarded as a monophyletic clade as the s ...
. * A study on the use of quadrapediality in ''
Scutellosaurus ''Scutellosaurus'' ( ) is a genus of basal thyreophoran dinosaur that lived approximately 196 million years ago during the early part of the Jurassic Period in what is now Arizona, USA. It is classified in Thyreophora, the armoured dinosaurs; ...
lawleri'', and on its implications for locomotor behavior evolution in dinosaurs, is published by Anderson ''et al''. (2023), who interpret ''Scutellosaurus'' as mainly being a biped, and suggest quadrapediality was used during specific activities. *
Galton Sir Francis Galton (; 16 February 1822 – 17 January 1911) was an English polymath and the originator of eugenics during the Victorian era; his ideas later became the basis of behavioural genetics. Galton produced over 340 papers and b ...
(2023) describes a right sternal bone of a specimen of ''
Stegosaurus ''Stegosaurus'' (; ) is a genus of herbivorous, four-legged, armored dinosaur from the Late Jurassic, characterized by the distinctive kite-shaped upright plates along their backs and spikes on their tails. Fossils of the genus have been fo ...
'' from the Carnegie Quarry at
Dinosaur National Monument Dinosaur National Monument is an American national monument located on the southeast flank of the Uinta Mountains on the border between Colorado and Utah at the confluence of the Green River (Colorado River tributary), Green and Yampa River, Y ...
(
Morrison Formation The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltston ...
;
Utah Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
) and reevaluates three putative sternal bones from
Como Bluff Como Bluff is a long ridge extending east–west, located between the towns of Rock River and Medicine Bow, Wyoming. The ridge is an anticline, formed as a result of compressional geological folding. Three geological formations, the Sundance, ...
(
Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...
, United States) described by
Gilmore Gilmore or Gillmore may refer to: *Gilmore (surname) Places Australia *Gilmore, Australian Capital Territory, a suburb in the Canberra district of Tuggeranong * Gilmore Avenue, a road in southern Perth, Western Australia *Division of Gilmore, a ...
(1914), arguing that they are neither sternal bones nor fossils of ''Stegosaurus''. *Description of
nodosaurid Nodosauridae is a family of ankylosaurian dinosaurs known from the Late Jurassic to the Late Cretaceous periods in what is now Asia, Europe, North America, and possibly South America. While traditionally regarded as a monophyletic clade as the s ...
osteoderms from the Late Cretaceous
Snow Hill Island Formation The Snow Hill Island Formation is an Maastrichtian, Early Maastrichtian geologic Formation (geology), formation found on James Ross Island, James Ross Island group, Antarctica. Remains of a Paraves, paravian Theropoda, theropod ''Imperobator anta ...
(
Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...
) is published by Brum ''et al''. (2023), who suggest that osteoderm structure may have helped nodosaurids colonize high-latitude environments more easily. * Yoshida, Kobayashi &
Norell Norell is a surname. Notable people with the surname include: * Arne Norell (1917–1971), Swedish furniture designer *Ingeborg Norell (born 1727), the first Finnish female to have received an official decoration *Mark Norell (born 1957), American ...
(2023) report the discovery of fossilized larynx of a specimen of '' Pinacosaurus grangeri'' from the Campanian of Ukhaa Tolgod (
Mongolia Mongolia is a landlocked country in East Asia, bordered by Russia to the north and China to the south and southeast. It covers an area of , with a population of 3.5 million, making it the world's List of countries and dependencies by po ...
), and interpret its anatomy as indicating that ''Pinacosaurus'' might have been capable of vocalization and, like extant birds, might have possessed a non-laryngeal vocal source and used larynx as a sound modifier. * Tumanova ''et al.'' (2023) describe anomalies within the airway and sinuses of a skull of a specimen of ''
Tarchia ''Tarchia'' (meaning "brainy one") is a genus of herbivorous ankylosauridae, ankylosaurid dinosaur from the late Cretaceous of Mongolia. Discovery and naming In 1970, a Polish-Mongolian expedition discovered an ankylosaurian skull near Khulsan. ...
'', which were only detected while CT scanning the specimen, and which might have been caused by infection and/or trauma. * A study on the cranial biomechanics of '' Panoplosaurus mirus'' and ''
Euoplocephalus tutus ''Euoplocephalus'' ( ) is a genus of large herbivorous ankylosaurid dinosaurs, living during the Late Cretaceous of Canada. It has only one named species, ''Euoplocephalus tutus''. The first fossil of ''Euoplocephalus'' was found in 1897 in Albe ...
'' is published by Ballell, Mai & Benton (2023), who find evidence of differences interpreted as indicative of relatively higher bite forces in ''Panoplosaurus'', as well as indicative of stronger reinforcement of the skull of ''Euoplocephalus'', consistent with highly defensive function.


Cerapod research

* Evidence of significantly rougher dental microwear texture in Late Cretaceous
ornithopods Ornithopoda () is a clade of ornithischian dinosaurs, called ornithopods (). They represent one of the most successful groups of herbivore, herbivorous dinosaurs during the Cretaceous. The most primitive members of the group were bipedal and rel ...
compared to earlier members of the group, interpreted as indicative of dietary shift towards more abrasive foodstuffs, is presented by Kubo ''et al.'' (2023). * Review of the diversity, relationships, biogeography and paleoecology of rhabdodontids is published by Augustin, Ősi & Csiki-Sava (2023). * New rhabdodontid fossil material, possibly representing a taxon distinct from known Transylvanian rhabdodontids, is described from the Maastrichtian Densuș-Ciula Formation (Hațeg Basin;
Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...
) by Magyar ''et al.'' (2023). * Redescription of '' Cumnoria prestwichii'' is published by Maidment ''et al.'' (2023), who recover ''Cumnoria'' as a non-
ankylopollexia Ankylopollexia is an extinct clade of ornithischian dinosaurs that lived from the Late Jurassic to the Late Cretaceous. It is a derived clade of iguanodontian ornithopods and contains the subgroup Styracosterna. The name stems from the Greek wo ...
n
iguanodontia Ornithopoda () is a clade of ornithischian dinosaurs, called ornithopods (). They represent one of the most successful groups of herbivorous dinosaurs during the Cretaceous. The most primitive members of the group were bipedal and relatively sm ...
n, and consider it to be distinct from ''
Camptosaurus ''Camptosaurus'' ( ) is a genus of plant-eating, beaked ornithischian dinosaurs of the Late Jurassic Period (geology), period of western North America and possibly also Europe. The name means 'flexible lizard' (Ancient Greek, Greek (') meaning ...
''. * Rotatori ''et al.'' (2023) report the presence of a rich neurovascular network in the dentary of a
dryosaurid Dryosauridae was a family of primitive iguanodonts, first proposed by Milner & Norman in 1984. They are known from Middle Jurassic to Early Cretaceous rocks of Africa, Europe, and North America. Dryosauridae was first proposed in 1984 by Britis ...
from the Upper Jurassic
Lourinhã Formation The Lourinhã Formation () is a fossil-rich geological formation in western Portugal, named for the municipality of Lourinhã. The formation is mostly Late Jurassic in age (Kimmeridgian/Tithonian), with the top of the formation extending into the ...
(
Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...
), similar to vascularisation present in
cerapoda Neornithischia ("new ornithischians") is a clade of the dinosaur order Ornithischia. It is the sister group of the Thyreophora within the clade Genasauria. Neornithischians are united by having a thicker layer of asymmetrical enamel on the ins ...
n dinosaurs with high tooth replacement rates. * Redescription of the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
of '' Mantellisaurus atherfieldensis'' is published by Bonsor ''et al.'' (2023), who confirm ''Mantellisaurus'' to be distinct from ''
Iguanodon ''Iguanodon'' ( ; meaning 'iguana-tooth'), named in 1825, is a genus of iguanodontian dinosaur. While many species found worldwide have been classified in the genus ''Iguanodon'', dating from the Late Jurassic to Early Cretaceous, Taxonomy (bi ...
''. * García-Cobeña, Cobosa & Verdú (2023) describe bone and trace fossils of
styracosterna Ankylopollexia is an extinct clade of ornithischian dinosaurs that lived from the Late Jurassic to the Late Cretaceous. It is a derived clade of iguanodontian ornithopods and contains the subgroup Styracosterna. The name stems from the Greek word ...
n ornithopods from the Lower Cretaceous
El Castellar Formation The El Castellar Formation is a geological Formation (geology), formation in La Rioja and Teruel, Spain whose strata date back to the possibly the Valanginian to the Barremian stages of the Early Cretaceous. Dinosaur remains are among the fossils ...
and
Camarillas Formation The Camarillas Formation is a geological formation in the Teruel Province of Aragón, Spain whose strata date back to the Early Cretaceous (Barremian stage). The sandstones, mudstones and conglomerates of the formation, that due to syn-sedimen ...
(
Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
), including
manus Manus may refer to: Relating to locations around New Guinea *Manus Island, a Papua New Guinean island in the Admiralty Archipelago ** Manus languages, languages spoken on Manus and islands close by ** Manus Regional Processing Centre, an offshore ...
- pes track set from the Camarillas Formation indicative of quadrupedal locomotion, assigned to the ichnogenus ''
Caririchnium ''Caririchnium'' is an ichnogenus of ornithopod dinosaur footprint, belonging to either derived iguanodonts or basal hadrosauroids. It includes the species ''Caririchnium lotus'' from Lower Cretaceous Jiaguan Formation and ''C''. ''protohadrosau ...
'' and produced by large styracosternans related to ''Iguanodon''. * A study on the palynological sample from the matrix surrounding a specimen of ''Iguanodon bernissartensis'' from the new Palau-3 site in the Lower Cretaceous Morella Formation is published by Rodríguez-Barreiro ''et al.'' (2023), who interpret the studied specimen as living in a coastal open forest environment with a warm and humid climate; the authors also compare the habitat of the studied specimen with those from other ''I. bernissartensis''-bearing sites, and interpret ''I. bernissartensis'' as feeding mostly on fronds of ferns belonging to the families
Anemiaceae ''Anemia'' is a genus of ferns. It is the only genus in the family Anemiaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Alternatively, the genus may be placed as the only genus in the subfamily Anemioideae of a more broa ...
and
Cyatheaceae The Cyatheaceae are a family of ferns, the scaly tree ferns, one of eight families in the order Cyatheales in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Alternatively, the family may defined much more broadly (Cyatheaceae ...
, as well as on the foliage of members of the family
Cheirolepidiaceae Cheirolepidiaceae (also spelled Cheirolepidaceae) is an extinct family of conifers. They first appeared in the Triassic, and were a diverse and common group of conifers during most of the Mesozoic era, primarily at low latitudes, where they often ...
. * A study on the evolution of the dentary in hadrosauroids, providing evidence of changes during the transition from non-hadrosaurid hadrosauroids to saurolophids which probably enhanced food gathering and food processing abilities, is published by Söderblom ''et al.'' (2023). * Description of new hadrosaurid fossils from the Upper Cretaceous
Kakanaut Formation The Kakanaut Formation is a geological formation in Siberia, whose strata date back to the Late Cretaceous (Maastrichtian). Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel et al., 2004, pp.593-600 The ...
(Chukotka,
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
) and a study on their histology is published by Bapinaev ''et al.'' (2023), who interpret the studied fossils as possibly indicative of the presence of two hadrosaurid taxa in the Kakanaut fauna, and interpret the histology of the studied bones as possibly indicating that Arctic hadrosaurids of Chukotka were year-round residents of polar ecosystems. * Joubarne, Therrien & Zelenitsky (2023) describe extensive skin impressions in three hadrosaurid specimens from the
Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...
Dinosaur Park Formation The Dinosaur Park Formation is the uppermost member of the Belly River Group (also known as the Judith River Group), a major geologic unit in southern Alberta. It was deposited during the Campanian stage of the Late Cretaceous, between about 7 ...
(
Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...
,
Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
), with two specimens preserving integument of the
manus Manus may refer to: Relating to locations around New Guinea *Manus Island, a Papua New Guinean island in the Admiralty Archipelago ** Manus languages, languages spoken on Manus and islands close by ** Manus Regional Processing Centre, an offshore ...
showing that their digits II–III–IV were approximately equal in length and united in a common fleshy structure, and the third specimen preserving scale stripes on its torso which might have corresponded to color stripes in life. * A study on the cranial suture interdigitation in Hadrosaurids, using data gathered from ''
Gryposaurus ''Gryposaurus'' (meaning "hooked-nosed (Ancient Greek, Greek ''grypos'') lizard"; sometimes incorrectly translated as "griffin (Latin ''gryphus'') lizard") was a genus of hadrosaur, duckbilled dinosaur that lived about 80 to 75 million years ag ...
'' and ''
Corythosaurus ''Corythosaurus'' (; ) is a genus of hadrosaurid "duck-billed" dinosaur from the Late Cretaceous Period (geology), period, about 77–75.7 million years ago, in what is now Laramidia, western North America. Its name is derived from the Anci ...
'' is published by Dudgeon and Evans (2023) who find that suture interdigitation increased across Hadrosaurid
ontogeny Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the ovum, egg to adult. The term can also be used to refer to t ...
, that Lambeosaurines had higher suture interdigitation than other Iguanodontians, and that increased suture complexity coincided with Lambeosaurine crest evolution. * Currie, & Wang (2023) describe the maxilla of a juvenile lambeosaurine (likely either ''Corythosaurus'' or ''
Lambeosaurus ''Lambeosaurus'' ( ) is a genus of hadrosaurid dinosaur that lived during the Late Cretaceous period of western North America. The first skull of ''Lambeosaurus'' found was used by palaeontologist Lawrence M. Lambe to justify the creation of ...
'') from the
Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...
Dinosaur Park Formation (Alberta, Canada), compare it with the maxilla of a probable juvenile hadrosaurine (possibly ''Gryposaurus'') from a different bonebed from the same formation, and interpret these fossils as indicating that lambeosaurines and hadrosaurines had similar tooth counts at hatching, which subsequently diverged during ontogeny. * Description of the anatomy of the postcranial skeleton of '' Laiyangosaurus youngi'' is published by Zhang ''et al.'' (2023). * Seymour ''et al.'' (2023) estimate blood flow rates to the tibia shafts of '' Maiasaura peeblesorum'', and report higher flow rates in juveniles which were likely related to higher oxygen demand for bone growth in juveniles compared to maintenance and repair of bone tissue damage in adults. * A study on the anatomy of the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
specimen of '' Gravitholus albertae'' is published by Dyer, Powers &
Currie Currie is a village and suburb on the outskirts of Edinburgh, Scotland, situated south west of the city centre. Formerly within the County of Midlothian, it now falls within the jurisdiction of the City of Edinburgh Council. It is situated be ...
(2023), who interpret both ''Gravitholus albertae'' and ''
Hanssuesia sternbergi ''Hanssuesia'' is a genus of pachycephalosaurid dinosaurs from the late Cretaceous period. It lived in what is now Alberta and Montana, and contains the single species ''Hanssuesia sternbergi''. ''Hanssuesia'' is based on a skull dome originally ...
'' as likely
junior synonyms In taxonomy, the scientific classification of living organisms, a synonym is an alternative scientific name for the accepted scientific name of a taxon. The botanical and zoological codes of nomenclature treat the concept of synonymy differently. ...
of ''
Stegoceras validum ''Stegoceras'' is a genus of pachycephalosaurid (dome-headed) dinosaur that lived in what is now North America during the Late Cretaceous period, about 77.5 to 74 million years ago (mya). The first specimens from Alberta, Canada, were descr ...
''. * Han ''et al.'' (2023) describe entangled specimens of '' Psittacosaurus lujiatunensis'' and '' Repenomamus robustus'' from the Lujiatun Member of the
Yixian Formation The Yixian Formation (; formerly Romanization of Chinese, transcribed as Yihsien Formation or Yixiang Formation) is a geological formation in Jinzhou, Liaoning, People's Republic of China, that spans the Barremian stage of the Early Cretaceous. I ...
(
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
), and interpret the studied specimens as likely locked in combat as a result of the predation attempt on the part of the mammal. * A study on the endocranial morphology of '' Liaoceratops yanzigouensis'' is published by Yang ''et al.'' (2023), who find that the brain, olfactory bulb and inner ear of ''Liaoceratops'' more closely resemble those observed in ''Psittacosaurus'' than those in more derived ceratopsians. * A review of the cranial evolution in
Ceratopsia Ceratopsia or Ceratopia ( or ; Ancient Greek, Greek: "horned faces") is a group of herbivore, herbivorous, beaked dinosaurs that thrived in what are now North America, Asia and Europe, during the Cretaceous Period (geology), Period, although ance ...
is published by Nabavizadeh (2023). * Chiba ''et al.'' (2023) provide evidence of the presence of frill margin undulations in ''
Protoceratops andrewsi ''Protoceratops'' (; ) is a genus of small protoceratopsid dinosaurs that lived in Asia during the Late Cretaceous, around 75 to 71 million years ago. The genus ''Protoceratops'' includes two species: ''P. andrewsi'' and the larger ''P. helleni ...
'', and interpret the undulated frill margin as possible shared feature in protoceratopsids or even
Coronosauria Ceratopsia or Ceratopia ( or ; Ancient Greek, Greek: "horned faces") is a group of herbivore, herbivorous, beaked dinosaurs that thrived in what are now North America, Asia and Europe, during the Cretaceous Period (geology), Period, although ance ...
. * Berry (2023) interprets the fossil record of late
Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...
ceratopsids from western North America as indicative of a significant rate of
background extinction Background extinction rate (BER), also known as the normal extinction rate, refers to the standard rate of extinction in Earth's geological and biological history, excluding major extinction events, including the current human-induced Holocene ex ...
approximately 76 million years ago, and interprets this pattern as most likely caused by competition for shared resources by
sympatric In biology, two closely related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter each other. An initially interbreeding population that splits into two or more distinct spe ...
ceratopsid species. *The development and homology of epiparietals (P1 and P2) in three ''
Centrosaurus ''Centrosaurus'' ( ; ) is a genus of centrosaurine ceratopsian dinosaur from Campanian age of Late Cretaceous Canada. Their remains have been found in the Dinosaur Park Formation, dating from 76.5 to 75.5 million years ago. Discovery and nami ...
'' specimens are described by Mallon, Holmes & Rufolo (2023), who suggest that these are separate ossifications that fuse with the parietal at different stages of
ontogeny Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the ovum, egg to adult. The term can also be used to refer to t ...
. * A study on the bone histology of ''
Triceratops ''Triceratops'' ( ; ) is a genus of Chasmosaurinae, chasmosaurine Ceratopsia, ceratopsian dinosaur that lived during the late Maastrichtian age of the Late Cretaceous Period (geology), period, about 68 to 66 million years ago on the island ...
'', providing evidence of a relatively fast and continuous growth rate, is published by de Rooij ''et al.'' (2023). * A study on the range of shoulder motion and on the orientation of the long bones of the forelimb of ''
Thescelosaurus ''Thescelosaurus'' ( ) is a genus of Ornithischia, ornithischian dinosaur that lived during the Late Cretaceous period (geology), period in western North America. It was named and described in 1913 by the Paleontology, paleontologist Charles W. G ...
'' and ''
Styracosaurus ''Styracosaurus'' ( ; meaning "spiked lizard" from the Ancient Greek / "spike at the butt-end of a spear-shaft" and / "lizard") is an extinct genus of herbivorous ceratopsian dinosaur from the Late Cretaceous (Campanian stage) of North America. ...
'' is published by Senter & Mackey (2023).


Birds


New bird taxa


Avian research

* A study on the evolution of limbs along avialan stem lineages is published by Wang & Zhou (2023), who provide evidence of a shift to low disparity and decelerated evolutionary rates near the origin of avialans, and interpret this shift as related to the evolutionary constrains on the morphology of the forelimb necessary for powered flight. * Macaulay ''et al.'' (2023) report that, in spite of the differences of body shape, there is overall no difference in the position of whole-body centre-of-mass between birds and non-avian theropods, but rather that there is such difference between hindlimb-dominated predominantly terrestrial taxa and forelimb-dominated predominantly volant taxa regardless of their phylogenetic placement, and argue that the fully crouched bipedalism seen in modern birds evolved after powered flight. * A study comparing dentin and enamel microstructure in ''Microraptor'', ''Anchiornis'', ''Sapeornis'' and ''Longipteryx'', providing evidence of microscopic modifications in tooth enamel, dentin and cementum between early birds and other theropods, as well as previously unrecognized plasticity in the developmental mechanisms controlling tooth microstructure in Mesozoic toothed birds, is published by Wang ''et al.'' (2023). * Kiat &
O'Connor O'Connor or O'Conor may refer to: People * O'Connor or O'Conor, an Irish clan * O'Connor Sligo, a royal dynasty ruling the northern part of the Kingdom of Connacht * O'Connor (surname), including a list of people with the surname Places * Burdett ...
(2023) reevaluate evidence of
molt In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at ...
in the fossil record of birds and non-avian dinosaurs, report rarity of molt occurrence both in the fossil record and in collections of extant bird species with simultaneous molts, and argue that the flight feather annual molt evolved with the development of powered flight, possibly only among crown birds. * Hong ''et al.'' (2023) describe a footprint assigned to the ichnospecies '' Wupus agilis'' from the Cretaceous Daegu Formation, representing the largest bird footprint from
South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia. It constitutes the southern half of the Korea, Korean Peninsula and borders North Korea along the Korean Demilitarized Zone, with the Yellow Sea to the west and t ...
described to date, report that ichnotaxa intermediate between non-avian theropod and unwebbed Mesozoic bird ichnotaxa generally show high morphological similarity with bird ichnospecies, and argue that these intermediate ichnotaxa might represent the ichnological record of large Mesozoic birds. * The oldest bird tracks from
Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...
reported to date are described from the Lower Cretaceous "
Wonthaggi Formation The Wonthaggi Formation is an informal geological Formation (geology), formation in Victoria, Australia whose strata date back to the Early Cretaceous. It is part of the Strzelecki Group within the Gippsland Basin. Dinosaur remains are among the ...
" (
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
) by Martin ''et al.'' (2023). * Wu ''et al.'' (2023) study the
phytolith Phytoliths (from Greek language, Greek, "plant stone") are rigid, microscopic mineral deposits found in some plant tissues, often persisting after the decay of the plant. Although some use "phytolith" to refer to all mineral secretions by plants, ...
s preserved in the stomach contents of a specimen of ''
Jeholornis prima ''Jeholornis'' (meaning "Jehol bird") is a genus of avialan dinosaurs that lived between approximately 122 and 120 million years ago during the early Cretaceous Period in China. Fossil ''Jeholornis'' were first discovered in the Jiufotang Formati ...
'', interpreting them as indicating that ''Jeholornis'' likely ate leaves of plants from the magnoliid angiosperm clade. * Five specimens of ''
Sapeornis ''Sapeornis'' is a monotypic genus of avialan dinosaurs which lived during the early Cretaceous period ( late Barremian to early Aptian, roughly 125-120 mya). ''Sapeornis'' contains only one species, ''Sapeornis chaoyangensis''. Description ...
chaoyangensis'' with different-preserved feathers are reported from the
Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...
Jehol Biota The Jehol Biota includes all the living organisms – the ecosystem – of northeastern China between 133 and 120 million years ago. This is the Lower Cretaceous ecosystem which left fossils in the Yixian Formation and Jiufotang Formation. These d ...
(
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
) by Zhao ''et al.'' (2023), who examine their implications for the taphonomy of soft tissues from the Jehol Biota. * Evidence from the study of well-preserved specimen of '' Confuciusornis sanctus'', interpreted as indicating that this bird was capable of prolonged flights as long as it alternated periods of high-efficiency gliding with active flapping, is presented by Chiappe ''et al.'' (2023). * An
enantiornithine The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and c ...
specimen from the Lower Cretaceous
La Huérguina Formation The La Huérguina Formation (also known as the Calizas de La Huérguina Formation, La Huérguina Limestone Formation or as the Una Formation) is a geological Formation (geology), formation in Spain whose strata date back to the Barremian stage of ...
closely resembling ''
Concornis ''Concornis'' is a genus of enantiornithean birds which lived during the early Cretaceous period, in the late Barremian age about 125 million years ago. Its remains are known from the Calizas de La Huérgina Formation at Las Hoyas, Cuenca prov ...
'' is described by Nebreda ''et al.'' (2023). * O'Connor ''et al.'' (2023) describe feathers of a young enantiornithine individual from the Cretaceous amber from
Myanmar Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...
, and interpret this finding as indicating that immature enantiornithines rapidly molted body feathers. * Redescription and a study on the affinities of '' Dapingfangornis sentisorhinus'' is published by Wang ''et al.'' (2023). * A study aiming to determine the diets of members of the family
Pengornithidae Pengornithidae is a group of early Enantiornithes, enantiornithines from the early Cretaceous Period of China, with the putative member ''Falcatakely'' possibly extending this clade's range into the Late Cretaceous of Madagascar, and several puta ...
is published by Miller ''et al.'' (2023), who report that ''
Pengornis ''Pengornis'' is the largest known enantiornithean bird from the Early Cretaceous of northeast China. The name derives from "Peng", which refers to a mythological bird from Chinese folklore, and "-ornis", which means bird in Greek. ''Pengorni ...
'', ''
Parapengornis ''Parapengornis'' is an extinct genus of enantiornithean bird from the Lower Cretaceous of what is now China. The holotype specimen was discovered in the Jiufotang Formation near Lingyuan, western Liaoning province, and was catalogued as IVPP V ...
'' and '' Yuanchuavis'' show adaptations for vertebrate carnivory. * Wang (2023) describes a new specimen of '' Parabohaiornis martini'' with a well-preserved skull from the Lower Cretaceous
Jiufotang Formation The Jiufotang Formation () is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms (see Jehol Biota). It is a member of the Jehol group. T ...
(
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
), and reports the presence of the
plesiomorphic In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all members of a clade, which does not distinguish the clade from other clades. Plesiomorphy, symplesiomorphy, apomorphy, an ...
temporal and
palatal The palate () is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but in most other tetrapods, the oral and nasal cavities are not truly sepa ...
configurations (similar to those of non-avian dinosaurs) in the skull of ''Parabohaiornis''. * Clark ''et al.'' (2023) attempt to determine the dietary habits of
longipterygids Longipterygidae is a Family (biology), family of early enantiornithean avialans from the Early Cretaceous epoch of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125-120 million ...
, reporting dental features indicative of carnivory, with additional support for insectivory. * A study on the gastral mass preserved with specimens of ''
Archaeorhynchus ''Archaeorhynchus'' (meaning "ancient snout") is a genus of beaked avialans from the early Cretaceous period. A fossil of its only known species, ''Archaeorhynchus spathula'', was first reported in 2005 by Zhou & Zhang to have been found in Yix ...
'' and ''
Iteravis ''Iteravis'' ("journey bird") is an extinct genus of ornithuromorph avialan. It was found in the Yixian Formation and lived during the Early Cretaceous period of what is today the Liaoning Province of China. The type and only species is ''I. huchz ...
'', interpreted as indicative of the digestive system comparable to that of extant birds, is Liu ''et al.'' (2023). * Lowi-Merri ''et al.'' (2023) provide evidence of soaring and foot-propelled swimming capabilities of ''
Ichthyornis ''Ichthyornis'' (meaning "fish bird", after its fish-like vertebrae) is an extinct genus of toothy seabird-like ornithuran from the late Cretaceous period of North America. Its fossil remains are known from the chalks of Alberta, Alabama, Kansa ...
''. * Blood flow rates in the
femora The femur (; : femurs or femora ), or thigh bone is the only bone in the thigh — the region of the lower limb between the hip and the knee. In many four-legged animals the femur is the upper bone of the hindleg. The top of the femur fits in ...
of a variety of extinct and extant
avialan Avialae ("bird wings") is a clade containing the only living dinosaurs, the birds, and their closest relatives. It is usually defined as all theropod dinosaurs more closely related to birds (Aves) than to deinonychosaurs, though alternative defi ...
s are estimated by Hu ''et al.'' (2023). * The
visual field The visual field is "that portion of space in which objects are visible at the same moment during steady fixation of the gaze in one direction"; in ophthalmology and neurology the emphasis is mostly on the structure inside the visual field and it i ...
s of ''
Hesperornis ''Hesperornis'' (meaning "western bird") is a genus of cormorant-like Ornithuran that spanned throughout the Campanian age, and possibly even up to the early Maastrichtian age, of the Late Cretaceous period. One of the lesser-known discoverie ...
'' and extant foot-propelled diving birds are estimated by Pecsics & Csörgő (2023). * Zelenkov & Arkhangelsky (2023) describe new fossil material of Campanian hesperornithids from the Karyakino locality (
Saratov Oblast Saratov Oblast is a federal subjects of Russia, federal subject of Russia (an oblast), located in the Volga Federal District. Its administrative center is the types of inhabited localities in Russia, city of Saratov. As of the 2021 Russian cens ...
,
Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
), including the first femur of '' Hesperornis rossicus''. * A
synsacrum The synsacrum is a skeletal structure of birds and other dinosaurs, pterosaurs, as well as xenarthran mammals, in which the sacrum is extended by incorporation of additional fused or partially fused caudal or lumbar In tetrapod anatomy, lum ...
and a
tarsometatarsus The tarsometatarsus is a bone that is only found in the lower leg of birds and some non-avian dinosaurs. It is formed from the fusion of several bird bones found in other types of animals, and homologous to the mammalian tarsus (ankle bones) a ...
assigned to the Vegaviidae from the Upper Cretaceous
López de Bertodano Formation The Lopez de Bertodano Formation is a geological Formation (geology), formation in the James Ross Island, James Ross archipelago of the Antarctic Peninsula. The strata date from the end of the Late Cretaceous (upper-lower Maastrichtian stage) to t ...
(
Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...
) are described by de Souza ''et al.'' (2023). * A study on the anatomy of the articular region of the lower jaw of ''
Vegavis iaai ''Vegavis'' is a genus of extinct bird that lived in Antarctica during the Maastrichtian stage of the Late Cretaceous. The type and only species is ''Vegavis iaai'', representing one of the earliest known crown group birds. Initially described ...
'' is published by Álvarez-Herrera ''et al.'' (2023), who report the presence of anatomical features shared with modern neornithine birds, and particularly with members of the
neoavian Neoaves is a clade that consists of all modern birds (Neornithes or Aves) with the exception of Palaeognathae (ratites and kin) and Galloanserae (ducks, chickens and kin). This group is defined in the ''PhyloCode'' by George Sangster and colleag ...
clade Aequorlitornithes. * Acosta Hospitaleche, O'Gorman & Panzeri (2023) describe a partial ulna of a bird (comparable in size with ulnae of the
coscoroba swan The coscoroba swan (''Coscoroba coscoroba'') is a species of waterfowl in the subfamily Anserinae of the family Anatidae.HBW and BirdLife International (2021) Handbook of the Birds of the World and BirdLife International digital checklist of the ...
or the
southern screamer The southern screamer (''Chauna torquata'') is a species of bird in family Anhimidae of the waterfowl order Anseriformes. It is found in Argentina, Bolivia, Brazil, Paraguay, Peru, and Uruguay.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. ...
) from the Maastrichtian
La Colonia Formation The La Colonia Formation is a geological Formation (geology), formation in Argentina whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel et al., 2004, pp.600- ...
(Argentina), showing similarities to ulnae of members of Anseriformes and possibly representing the first record of a neornithine from the La Colonia Formation. * Evidence from the study of eggshell fragments of '' Diamantornis laini'' from the Marsawdad Formation (
Oman Oman, officially the Sultanate of Oman, is a country located on the southeastern coast of the Arabian Peninsula in West Asia and the Middle East. It shares land borders with Saudi Arabia, the United Arab Emirates, and Yemen. Oman’s coastline ...
), interpreted as indicating that the deposits containing the eggshells are approximately 8-7 million years old, is presented by
Pickford Pickford is a surname, and may refer to * Sir Alfred Pickford (1872–1947), Scouting luminary and friend of Lord Baden-Powell * Charlotte Hennessey (1873–1928), aka Charlotte Smith Pickford, Canadian-American actress, mother of Mary, Lottie, and ...
''et al.'' (2023). * Mourer-Chauviré, Pickford & Senut (2023) describe new fossil material of ''
Struthio coppensi ''Struthio coppensi'' is an extinct species of ostrich located near Elisabethfeld, Namibia. This ostrich is believed to have lived during the Miocene, about 20 mya, and is the oldest member of the '' Struthio'' genus Genus (; : genera ) is a ...
'' from the Miocene sites in the Sperrgebiet (
Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ...
). * Buffetaut (2023) reports the discovery of a plaster cast of the lost femur of ''Struthio anderssoni'' from the late Pleistocene deposits of the Upper Cave at
Zhoukoudian Zhoukoudian Area () is a town and an area located on the east Fangshan District, Beijing, China. It borders Nanjiao and Fozizhuang Townships to its north, Xiangyang, Chengguan and Yingfeng Subdistricts to its east, Shilou and Hangcunhe Towns to ...
(China), and transfers the species ''S. anderssoni'' to the genus ''
Pachystruthio ''Pachystruthio'' is a genus of extinct bird which lived in Eurasia from the Late Pliocene to the Middle Pleistocene. Its fossils have been found in Hungary, Greece Crimea, Georgia (country), Georgia, and China. The genus contains three species: ...
''. * The body mass and running speed of '' Opisthodactylus kirchneri'' are estimated by Jones, Vezzosi & Blanco (2023). * A study on the evolutionary history of the elephant birds, based on data from fossil eggshells, is published by Grealy ''et al.'' (2023), who interpret their findings as supporting the placement of ''
Mullerornis ''Mullerornis modestus'' is an extinct species of elephant bird, and the only member of the genus ''Mullerornis''. Taxonomy The genus is named after Georges Muller, a French explorer, who was killed in 1892 by hostile members of the Sakalava pe ...
'' into a separate family, as well as indicative of the existence of a genetically distinct lineage of '' Aepyornis'' in Madagascar's far north, report evidence of divergence within ''Aepyornis'' corresponding with the onset of the Quaternary, and tentatively advocate synonymising ''Vorombe titan'' with ''Aepyornis maximus''. * Tracks made by
moa Moa are extinct giant flightless birds native to New Zealand. Moa or MOA may also refer to: Arts and media * Metal Open Air, a Brazilian heavy metal festival * MOA Museum of Art in Japan * The Moas, New Zealand film awards People * Moa ...
from the Pliocene–Pleistocene Maniototo Conglomerate Formation (
New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
) are described by Fleury ''et al.'' (2023). * A study on the formation of the
rhamphotheca The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for pecking, grasping, and holding (in probing for food, eating, manipulating and ca ...
in the middle-latest Eocene Antarctic pelagornithids is published by Piro & Acosta Hospitaleche (2023). * A study on the histology of long bones of '' Lutetodontopteryx tethyensis'' and
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
''
Dasornis ''Dasornis'' is a genus of prehistoric pseudotooth birds. These were probably close relatives of either pelicans and storks or waterfowl; they are placed in the order Odontopterygiformes to account for this uncertainty. Almost all known mater ...
'' sp. from the Eocene (
Lutetian The Lutetian is, in the geologic timescale, a stage (stratigraphy), stage or age (geology), age in the Eocene. It spans the time between . The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it ...
) locality Ikove (
Luhansk Oblast Luhansk Oblast (; ), also referred to as Luhanshchyna (), is the easternmost Administrative divisions of Ukraine, oblast (province) of Ukraine. Its administrative center is the city of Luhansk. The oblast was established in 1938 and bore the n ...
) is published by Dobrovolsky (2023). * Aspects of the life history of '' Lutetodontopteryx tethyensis'' and
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
''
Dasornis ''Dasornis'' is a genus of prehistoric pseudotooth birds. These were probably close relatives of either pelicans and storks or waterfowl; they are placed in the order Odontopterygiformes to account for this uncertainty. Almost all known mater ...
'' sp. are inferred based on bone histology by Dobrovolsky & Gorobets (2023). * The impact of including fossil taxa on inferring the ancestral morphology of the quadrate in Galloanserae is studied by Kuo, Benson & Field (2023). * Revision of small-bodied ducks from the Miocene localities in France and Mongolia is published by Zelenkov (2023), who transfers the species ''Anas velox'' to the genus '' Protomelanitta'' and transfers the species ''Anas soporata'' to the genus ''
Mioquerquedula ''Mioquerquedula'' is an extinct genus of ducks from the Middle Miocene containing two species, ''M. minutissima'' and ''M. velox''. It was one of the smallest anseriforms known. The genus was erected by Nikita Zelenkov and Evgenii Nik ...
''. * Fossils of
hazel grouse The hazel grouse (''Tetrastes bonasia''), sometimes called the hazel hen, is one of the smaller members of the grouse family of birds. It is a sedentary species, breeding across the Palearctic as far east as Hokkaido, and as far west as eastern a ...
from the Quaternary of
Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...
are documented by Boev (2023). * Mayr ''et al.'' (2023) describe bird cervical vertebrae from the Quercy fissure fillings (
France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
), densely covered with tubercles similar to those reported in members of the genus '' Perplexicervix'' and in ''"Dynamopterus" tuberculatus'' from the
Messel pit The Messel Formation is a Formation (geology), geologic formation in Hesse, central Germany, dating back to the Eocene Epoch (geology), epoch (about 47 Ma). Its geographic range is restricted to the Messel pit. There it unconformably overlie ...
in
Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...
as well as in extant
maned rat The maned rat or (African) crested rat (''Lophiomys imhausi'') is a nocturnal, long-haired and bushy-tailed East African rodent that superficially resembles a porcupine. The world's only known poisonous rodent, the maned rat sequesters toxins fro ...
, and interpret these tubercles as a feature of distinctive clade of Eocene birds (Perplexicervicidae), possibly representing an anti-predator adaptation against the killing bite of mammalian carnivores. * An
egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the ...
belonging to a
flamingo Flamingos or flamingoes () are a type of wading bird in the family Phoenicopteridae, which is the only extant family in the order Phoenicopteriformes. There are four flamingo species distributed throughout the Americas (including the Caribbe ...
from the Pleistocene of
Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...
is described by Cruz ''et al.'' (2023). * Fossils of small
rails Rail or rails may refer to: Rail transport *Rail transport and related matters * Railway track or railway lines, the running surface of a railway Arts and media Film * ''Rails'' (film), a 1929 Italian film by Mario Camerini * ''Rail'' (1967 fi ...
from the late Pleistocene and early Holocene of the Southern High Plains are described by Moretti & Johnson (2023). * The evolutionary history of the
takahē The South Island takahē (''Porphyrio hochstetteri'') is a Flightless bird, flightless swamphen indigenous to New Zealand and the largest living member of the Rail (bird), rail family. It is often known by the abbreviated name takahē, whic ...
and
moho Moho may refer to: Birds * ''Moho'' (genus), an extinct genus of birds in the family Mohoidae * The Hawaiian name of the Hawaiian rail, an extinct species * The Māori name of the North Island takahē, an extinct species * A local name for the o ...
are inferred through analyses of ancient
mitochondrial genome Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in ...
s by Verry ''et al.'' (2023). * A study of Pleistocene fossils from the Naracoorte Caves (
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
) by Lenser & Worthy (2023) confirmed the presence of
plains-wanderer The plains-wanderer (''Pedionomus torquatus'') is an atypical species of wading bird, the only representative of family Pedionomidae and genus ''Pedionomus''. It is endemic to Australia. Its historic range included much of eastern Australia, i ...
in the fossil assemblages at this site, and suggests that this species formerly inhabited
forest A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, ...
and
woodland A woodland () is, in the broad sense, land covered with woody plants (trees and shrubs), or in a narrow sense, synonymous with wood (or in the U.S., the '' plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunli ...
environments. * Fossils of the
red-throated loon The red-throated loon (North America) or red-throated diver (Britain and Ireland) (''Gavia stellata'') is a migratory aquatic bird found in the northern hemisphere. The most widely distributed member of the loon or diver family, it breeds prim ...
and an undetermined species of '' Gavia'' are described from the Pleistocene Liuchungchi Formation (Taiwan) by Wu ''et al.'' (2023), representing the first Pleistocene records of Gaviidae in the subtropical Northwest Pacific reported to date. *
Ecomorphology Ecomorphology or ecological morphology is the study of the relationship between the ecological, ecological role of an individual and its morphology (biology), morphological adaptations. The term "morphological" here is in the anatomical context. Bo ...
of the
penguin Penguins are a group of aquatic flightless birds from the family Spheniscidae () of the order Sphenisciformes (). They live almost exclusively in the Southern Hemisphere. Only one species, the Galápagos penguin, is equatorial, with a sm ...
wing is studied by Haidr (2023), finding that ''
Madrynornis ''Madrynornis'' is an extinct monotypic genus of spheniscid containing the species ''M. mirandus'' that inhabited Argentina during the Late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), E ...
'' resembled extant
piscivorous A piscivore () is a carnivorous animal that primarily eats fish. Fish were the diet of early tetrapod evolution (via water-bound amphibians during the Devonian period); insectivory came next; then in time, the more terrestrially adapted rept ...
penguins in its wing morphology. * A skull of a small penguin, possibly representing a new species belonging to the genus ''
Spheniscus The banded penguins are penguins that belong to the genus ''Spheniscus''. There are four living species, all with similar banded plumage-patterns. They are sometimes also known as "jack-ass penguins" due to their loud locator-calls sounding sim ...
'', ''
Eudyptula The genus ''Eudyptula'' ("good little diver") contains two species of penguin, found in southern Australia, Tasmania, and New Zealand (including the Chatham Islands). They are commonly known as the little penguin, little blue penguin, or, in Aus ...
'' or to a new genus ancestral to both listed genera, is described from the Miocene
Bahía Inglesa Formation The Bahía Inglesa Formation (alternatively misspelled "Bahia") is a littoral, sedimentary, and highly fossiliferous geological formation that outcrops across the nearby coastal zones of Caldera, Chile. The unit is part of the greater Caldera Basi ...
(
Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...
) by Acosta Hospitaleche & Soto-Acuña (2023). * Figueiredo ''et al''. (2023) report a partial
coracoid A coracoid is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is present as part of the scapula, but this is n ...
of the genus '' Morus'' from the middle
Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
(
Langhian The Langhian is, in the ICS geologic timescale, an age or stage in the middle Miocene Epoch/Series. It spans the time between 15.97 ± 0.05 Ma and 13.65 ± 0.05 Ma (million years ago) during the Middle Miocene.GeoWhen (2007) The Langhian was ...
) of the
Setúbal Peninsula The Setúbal Peninsula ( Portuguese: ) is a peninsula in the Lisbon Region of Portugal. The peninsula is named after one of its larger cities, Setúbal, and is bordered by three bodies of water, the Atlantic Ocean in the west and southwest, the T ...
(
Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...
), an instance that represents the first Miocene sulid described from the
Iberian Peninsula The Iberian Peninsula ( ), also known as Iberia, is a peninsula in south-western Europe. Mostly separated from the rest of the European landmass by the Pyrenees, it includes the territories of peninsular Spain and Continental Portugal, comprisin ...
. * Ksepka & Tennyson (2023) report the discovery of the humerus of a probable
stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technology, engineering, and mathematics Stem or STEM can also refer to: Language and writing * Word stem, part of a word respon ...
gannet from the Hurupi Formation, representing the oldest record of a sulid from
New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
reported to date. * Guilherme ''et al.'' (2023) describe fossil material of '' Macranhinga'' sp. and '' Anhinga minuta'' from the Acre conglomerate member in the southwestern Amazon region, suggesting the presence of potentially three distinct
darter The darters, anhingas, or snakebirds are mainly tropical waterbirds in the family Anhingidae, which contains a single genus, ''Anhinga''. There are four living species, three of which are very common and widespread while the fourth is rarer and c ...
taxa within the same locality during the late Miocene. * Osteological comparisons and historical accounts of recently extinct island night herons are presented by Hume (2023). * The relationship between skull morphology and feeding ecology of
vulture A vulture is a bird of prey that scavenges on carrion. There are 23 extant species of vulture (including condors). Old World vultures include 16 living species native to Europe, Africa, and Asia; New World vultures are restricted to Nort ...
s is studied by Steinfield ''et al.'' (2023), finding that '' Breagyps'' may have belonged to the "gulper" feeding guild, which specializes in feeding on the soft internal tissues of carcasses. *
Coprolite A coprolite (also known as a coprolith) is fossilized feces. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour (in this case, diet) rather than morphology. The name ...
s of
bearded vulture The bearded vulture (''Gypaetus barbatus''), also known as the lammergeier and ossifrage, is a very large bird of prey in the Monotypic taxon, monotypic genus ''Gypaetus''. The bearded vulture is the only known vertebrate whose diet consists of ...
s from the Pleistocene of
Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...
are described by Sanz ''et al.'' (2023). * A
tarsometatarsus The tarsometatarsus is a bone that is only found in the lower leg of birds and some non-avian dinosaurs. It is formed from the fusion of several bird bones found in other types of animals, and homologous to the mammalian tarsus (ankle bones) a ...
of a
cinereous vulture The cinereous vulture (''Aegypius monachus''), also known as the black vulture, Eurasian black vulture, and monk vulture, is a very large Raptor (bird), raptor in the family Accipitridae distributed through much of temperate Eurasia. With a body ...
from the Late Pleistocene Gansuiji Formation (
Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
) is described by Matsuoka & Hasegawa (2023), representing the first fossil record of this species from Japan. * Pellets and a fragmentary beak of a
barn owl The barn owls, owls in the genus '' Tyto'', are the most widely distributed genus of owls in the world. They are medium-sized owls with large heads and characteristic heart-shaped faces. They have long, strong legs with powerful talons. The ter ...
from the Holocene of
Socotra Island Socotra, locally known as Saqatri, is a Yemeni island in the Indian Ocean. Situated between the Guardafui Channel and the Arabian Sea, it lies near major shipping routes. Socotra is the largest of the six islands in the Socotra archipelago as ...
(
Yemen Yemen, officially the Republic of Yemen, is a country in West Asia. Located in South Arabia, southern Arabia, it borders Saudi Arabia to Saudi Arabia–Yemen border, the north, Oman to Oman–Yemen border, the northeast, the south-eastern part ...
) are reported by Ramello ''et al.'' (2023). * The first known
phorusrhacid Phorusrhacids, colloquially known as terror birds, are an extinct family of large carnivorous, mostly flightless birds that were among the largest apex predators in South America during the Cenozoic era. Their definitive fossil records range from ...
footprints are described from the Río Negro Formation (
Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
) by Melchor ''et al.'' (2023), who name a new ichnotaxon '' Rionegrina pozosaladensis'', and interpret the studied footprints as indicative of a primary role of digit III, secondary role of digit IV and a reduced role of digit II in body weight support. * Changes in the diversity of
amazon parrot Amazon parrots are parrots in the genus ''Amazona''. They are medium-sized, short-tailed parrots native to the Americas, with their range extending from South America to Mexico and the Caribbean. ''Amazona'' is one of the 92 genera of parrots t ...
s in the
Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America ...
are inferred through analyses of genetic sequences from ancient and modern specimens by Oswald ''et al.'' (2023). * Stidham, O'Connor & Li (2023) reexamine the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
of ''Corvus fangshannus'' and reinterpret it as a member of the sedentary Northern Raven (''Corvus corax'') lineage. * Baumann ''et al.'' (2023) report isotopic data from raven remains from early
Gravettian The Gravettian is an archaeological industry of the European Upper Paleolithic that succeeded the Aurignacian circa 33,000 years BP. It is archaeologically the last European culture many consider unified, and had mostly disappeared by   ...
sites in Southern Moravia (
Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...
), interpreted as indicating that the studied ravens consumed the same range of foods as contemporaneous Gravettian foragers, regularly feeding on larger herbivores and especially mammoths. * A review and update of the
Cenozoic The Cenozoic Era ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterized by the dominance of mammals, insects, birds and angiosperms (flowering plants). It is the latest of three g ...
fossil record of birds in
Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
is published by Tambussi, Degrange & de Mendoza (2023). * Mourer-Chauviré ''et al.'' (2023) describe fossil material of a songbird of uncertain affinities, a lovebird of uncertain specific assignment and
cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...
''Palaeortyx'' from the Miocene deposits at Grillental (
Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ...
), representing some of the earliest records of their respective groups in Africa reported to date. * Changes in body size of birds from the Yucatán peninsula since the Late Pleistocene are documented by Silva-Martínez ''et al.'' (2023). * Fossil material of birds from the Pleistocene of La Crouzade Cave (
France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
) is described by Garcia-Fermet ''et al.'' (2023). * Neto de Carvalho ''et al.'' (2023) describe an assemblage of bird trace fossils from a Pleistocene coastal aeolianite unit from the south-west
Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...
, including two new forms of traces: ''Corvidichnus odemirensis'', likely produced by the western jackdaw, and ''Buboichnus vicentinus'', attributed to the locomotion and feeding behaviour of a large eagle-owl. * Gala, Laroulandie & Lenoble (2024) revise the record of bird remains from the Guadeloupe Islands spanning the last 30,000 years, providing evidence of direct and indirect human impact on changes of local bird communities.


Pterosaurs


New pterosaur taxa


Pterosaur research

* A study on the diversification of pterosaurs during their evolutionary history, aiming to determine the factors that affected pterosaur evolution, is published by Yu, Zhang & Xu Xing (paleontologist), Xu (2023). * A study comparing the sternum, sternal anatomy of 60 different pterosaur species is published by Hone (2023). * Yang ''et al.'' (2023) compare wing ontogeny and performance in ''Rhamphorhynchus'', ''Pterodactylus'', ''Sinopterus'' and ''Pteranodon'', and interpret the differences in the growth patterns of the studied pterosaurs as suggestive of more Precociality and altriciality, altricial development in ''Pteranodon'' than in smaller-bodied pterosaurs. * Review of the fossil record of Jurassic and Cretaceous pterosaurs from
Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...
is published by Pentland & Poropat (2023). * Revision of the pterosaur assemblage from the Kem Kem Group (
Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...
) is published by Smith ''et al.'' (2023), who provide revised diagnoses for ''Afrotapejara, Afrotapejara zouhrii'' and ''Alanqa, Alanqa saharica'', and report at least three distinct jaw morphotypes which cannot be referred to any previously named species. * Jagielska ''et al.'' (2023) describe a non-pterodactyloid pterosaur specimen from the
Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...
Lealt Shale (Isle of Skye, Scotland,
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
), preserving metatarsal and caudal vertebrae which are considerably larger than corresponding bones in the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
of ''Dearc, Dearc sgiathanach''. * A study on the surface of the
holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...
specimen of ''Scaphognathus, Scaphognathus crassirostris'', providing evidence of the presence of six different types of Pterosaur#Pycnofibers, pycnofibers, is published by Henkemeier, Jäger & Sander (2023). * The oldest pterosaur remains found in
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
to date, including the first fossil material of a juvenile pterosaur from Australia, is described from the Lower Cretaceous Eumeralla Formation by Pentland ''et al.'' (2023). * A study on the microstructure of the tooth and periodontium attachment tissues of ''Pterodaustro, Pterodaustro guinazui'' is published by Cerda & Codorniú (2023), who report that teeth of this pterosaur were set in a groove with no interdental separation, and find no evidence for gomphosis or the presence of replacement teeth. * Pterosaur teeth which might represent the earliest record of Istiodactylidae reported to date are described from the
Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 137.05 ± 0.2 Ma and 132.6 ± 0.2 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretac ...
Wadhurst Clay Formation (
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
) by Sweetman (2023). * The geologically oldest specimen of ''Nurhachius'' reported to date is described from the Lower Cretaceous Jingangshan Member of the Yixian Formation (China) by Ozeki ''et al.'' (2023). * Description of the pectoral girdle morphology and histology in ''Hamipterus'', providing evidence of both the similarities and differences between the flight apparatus of pterosaurs and birds, is published by Wu ''et al.'' (2023). * A study on the microstructure of teeth of ''Hamipterus'', providing evidence of thin Tooth enamel, enamel that covered approximately half of the tooth crown, is published by Chen ''et al.'' (2023). * Richards, Stumkat & Salisbury (2023) describe a new specimen of the ''Thapunngaka'' from the Lower Cretaceous (Albian) Toolebuc Formation (Australia), consisting of parts of the premaxillary and maxillary Rostrum (anatomy), rostrum, and two new clades of tropeognathines, Mythungini and Tropeognathini. * Smith, Martill & Zouhri (2023) reinterpret a purported shark spine from the Cenomanian Cambridge Greensand Member of the West Melbury Marly Chalk Formation (Cambridgeshire, United Kingdom) as a jaw fragment of an Azhdarchoidea, azhdarchoid distinct from ''Ornithostoma, Ornithostoma sedgwicki'', but sharing a distinctive morphology with jaw fragments reported from the Kem Kem Beds of Morocco. * Song, Jiang & Wang (2023) redescribe purported dsungaripterid remains from the Lower Cretaceous (Albian) Doushan Formation (China), assign the most complete element (a femur) to Azhdarchoidea, and study osteological correlates for thigh muscles on the femur, interpreting their general pattern as conservative when compared with other basal ornithodirans. * New Jehol Tapejaridae, tapejarid skeleton, probably belonging to a specimen of ''Sinopterus, Sinopterus dongi'' and providing new information on the skull anatomy in this species, is described by Zhou, Miao & Andres (2023). * A study on the affinities of ''"Tupuxuara" deliradamus'' is published by Cerqueira, Müller & Pinheiro (2023), who interpret this pterosaur as a Tapejarinae, tapejarine. * A study on the ontogeny of ''Caiuajara, Caiuajara dobruskii'', as inferred from its bone histology, is published by de Araújo ''et al.'' (2023). * Fragmentary wing phalanges from the Aptian-Albian Antlers Formation (
Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...
,
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
), originally noted by Bennett (2001) to be similar in their oval cross-sections to those of ''Dsungaripterus'', are interpreted by Bennett (2023) as possible Thalassodrominae, thalassodromine fossil material. * Agnolín ''et al.'' (2023) report the discovery of a pterosaur cervical vertebra from the
Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...
Candeleros Formation (
Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
), interpreted as the oldest record of an Azhdarchidae, azhdarchid from South America reported to date. * Four teeth representing the first pterosaur material from Ukraine reported to date are described from the Lower Cretaceous Burim Formation by Sokolskyi (2023).


Other archosaurs


Other archosaur research

* Redescription of the skeletal anatomy of ''Scleromochlus, Scleromochlus taylori'' is published by Foffa ''et al.'' (2023), who interpret ''S. taylori'' as a Lagerpetidae, lagerpetid. * Description of the anatomy of the braincase of ''Dromomeron, Dromomeron gregorii'' is published by Bronzati ''et al.'' (2023), who also present reconstructions of soft tissues associated with the braincase, and report that sensory structures of ''D. gregorii'' were more similar to those of pterosaurs than to those of other early avemetatarsalians. * Mestriner ''et al.'' (2023) describe an assemblage of silesaurid remains from the Waldsanga locality from the Santa Maria Formation (Brazil), providing evidence of the presence of a combination of Dinosauromorpha, dinosauromorph Plesiomorphy and symplesiomorphy, symplesiomorphies and silesaurid diagnostic traits in the postcranial skeletons of the studied specimens.


General research

* Wang, Claessens & Sullivan (2023) establish skeletal features associated with the attachment of Uncinate processes of ribs, uncinate processes to vertebral ribs in extant birds and crocodilians, attempt to determine their distribution in fossil archosaurs, and interpret their findings as indicating that cartilaginous uncinate processes were Plesiomorphy and symplesiomorphy, plesiomorphically present (and likely had a ventilatory function) in dinosaurs, and maybe even in archosaurs in general. * Tito Aureliano, Aureliano ''et al.'' (2023) present the criteria which can be used to distinguish between lamellar bone fibres, Sharpey's fibres (tendon insertions) and air sac attachments in the bones of fossil archosaurs. * De-Oliveira ''et al.'' (2023) report the discovery of an isolated tooth from the São Luiz Site (Candelária Formation, Paraná Basin, Candelária Sequence;
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
), providing evidence of the presence of a previously unknown medium or large-sized carnivorous archosaur at the site. * Abrahams & Bordy (2023) reevaluate tracks assigned to the ichnogenus ''Trisauropodiscus'' from the Upper Triassic–Lower Jurassic
Elliot Formation The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup. Outcrops of the Elliot Formation have been found in the northern Eastern Cape, so ...
, and report that the studied material includes tracks produced by a yet-unknown tridactyl archosaur with a bird-like foot morphology. * Figueiredo ''et al.'' (2023) describe crocodylomorph and thyreophoran dinosaur tracks from the Lower Jurassic (
Sinemurian In the geologic timescale, the Sinemurian is an age (geology), age and stage (stratigraphy), stage in the Early Jurassic, Early or Lower Jurassic epoch (geology), Epoch or series (stratigraphy), Series. It spans the time between 199.5 ±0.3 annu ...
) Coimbra Formation (Portugal), and name a new ichnotaxon ''Moyenisauropus, Moyenisauropus lusitanicus''. * A possible didactyl deinonychosaurian track and an assemblage of pterosaur tracks is reported from the Jurassic Santai Formation (Shandong, China) by Xing ''et al.'' (2023). * Evidence indicative of
Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 137.05 ± 0.2 Ma and 132.6 ± 0.2 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretac ...
maximum age for the Urho Pterosaur Fauna from the Tugulu Group in Junggar Basin (Xinjiang, China) is presented by Zheng ''et al.'' (2023). * Juarez ''et al.'' (2023) corroborate the identification of
abelisaurid Abelisauridae (meaning "Abel's lizards") is a family (or clade) of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are foun ...
and Peirosauridae, peirosaurid teeth from the Upper Cretaceous Ciénaga del Río Huaco Formation, representing the first record of both groups from the Upper Cretaceous of the Precordillera of La Rioja (
Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
). * Putative
avialan Avialae ("bird wings") is a clade containing the only living dinosaurs, the birds, and their closest relatives. It is usually defined as all theropod dinosaurs more closely related to birds (Aves) than to deinonychosaurs, though alternative defi ...
teeth from the Late Cretaceous of
Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...
, Canada are reinterpreted as belonging to crocodylians by Mohr, Acorn & Currie (2023). * Taphonomic effects of fossilization on melanin in feathers are experimentally investigated by Roy ''et al.'' (2023). * Evidence from taphonomic experiments, interpreted as indicating that putative Alpha-keratin, keratins reported from fossil feathers are most likely artefacts of fossilization, but also indicating that Beta-keratin, corneous β-proteins of feathers can persist through deep time, is presented by Slater ''et al.'' (2023). * A review of the evolution of nest site use and nest architecture in avian and non-avian dinosaurs is published by Mainwaring ''et al.'' (2023). * Evidence of changes in eggshell structure throughout embryonic development of the broad-snouted caiman is presented by Fernández, Piazza & Simoncini (2023), who interpret their findings as potentially explaining the differences in porosity and thickness of dinosaur eggshells found at different levels in fossil deposits with broods.


References

{{reflist Archosaurs 2023 in paleontology