This list 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 preserved ...

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

s described in 2019 is a list of new

taxa In biology, a taxon ( back-formation from '' taxonomy''; plural 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 n ...

trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the ...

s, fossil

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs ...

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean gro ...

arachnid Arachnida () is a class of joint-legged invertebrate animals ( arthropods), in the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and ...

s and other fossil arthropods of every kind that are scheduled to be described during the year 2019, as well as other significant discoveries and events related to arthropod paleontology that are scheduled to occur in the year 2019.

General research

* A revision of higher-level arthropod taxonomy is published by Aria (2019), who proposes the name Cenocondyla for the least inclusive group containing both

Mandibulata Mandibulata, termed "mandibulates", is a clade of arthropods that comprises the extant subphyla Myriapoda (millipedes and others), Crustacea and Hexapoda (insects and others). Mandibulata is currently believed to be the sister group of the clade ...

and

Chelicerata The subphylum Chelicerata (from New Latin, , ) constitutes one of the major subdivisions of the phylum Arthropoda. It contains the sea spiders, horseshoe crabs, and arachnids (including harvestmen, scorpions, spiders, solifuges, ticks, and mite ...

. * A study on the molecular composition and microanatomy of the eyes of 54-million-year-old crane flies from the

Fur Formation The Fur Formation is a marine geological formation of Ypresian ( Lower Eocene Epoch, c. 56.0-54.5 Ma) age which crops out in the Limfjord region of Denmark from Silstrup via Mors and Fur to Ertebølle, and can be seen in many cliffs and quarries ...

(

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establishe ...

), evaluating its implications for the knowledge of optical systems of other ancient arthropods (especially trilobites), is published by Lindgren ''et al.'' (2019).

Arachnids

Research

* Two new specimens of laniatorid

harvestmen The Opiliones (formerly Phalangida) are an Order (biology), order of arachnids Common name, colloquially known as harvestmen, harvesters, harvest spiders, or daddy longlegs. , over 6,650 species of harvestmen have been discovered worldwide, alth ...

(an adult specimen assignable to the species ''

Proholoscotolemon ''Proholoscotolemon'' is an extinct genus of armoured harvestmen in the family Cladonychiidae The Cladonychiidae are a small family of harvestman with about 33 described species, within the suborder Laniatores. Description Members of this fa ...

nemastomoides'' and a smaller specimen belonging or related to the genus ''Proholoscotolemon'') are described from the

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

Baltic amber The Baltic region is home to the largest known deposit of amber, called Baltic amber or succinite. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that these forests created more than 1 ...

by Bartel & Dunlop (2019). * A review of the phylogenetic hypotheses of

scorpion Scorpions are predatory arachnids of the order Scorpiones. They have eight legs, and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always endi ...

interrelationships, as well as of scorpion palaeontology, is published by Howard ''et al.'' (2019), who also provide a list of scorpion fossil calibrations for use in molecular dating. * A fossil spider, possibly a juvenile female

golden silk orb-weaver ''Nephila'' is a genus of araneomorph spiders noted for the impressive webs they weave. ''Nephila'' consists of numerous species found in warmer regions around the world. They are commonly called golden silk orb-weavers, golden orb-weavers, gian ...

, is described from the Lower

Palana Formation Palana may refer to: * Palana, Bikaner, India * Palana, Kheda, India * Palana, Russia Palana (russian: Пала́на; Koryak: Ӄычг'эт, Пыльг'ыльг'ын) is an urban locality (an urban-type settlement) in Tigilsky District of K ...

of the Gurha opencast lignite mine (western

Rajasthan Rajasthan (; lit. 'Land of Kings') is a state in northern India. It covers or 10.4 per cent of India's total geographical area. It is the largest Indian state by area and the seventh largest by population. It is on India's northwestern s ...

India India, officially the Republic of India ( Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the ...

) by Patel, Rana & Selden (2019), representing the first fossil spider from India which wasn't found in amber. * A review of the fossil record and evolutionary history of spiders, reevaluating the phylogenetic placement of key fossils and aiming to determine whether there has been a major turnover in the spider fauna between the Mesozoic and Cenozoic, is published online by Magalhaes ''et al.'' (2019).

New taxa

Crustaceans

Research

* A global dataset of exceptionally preserved muscles and muscle attachment scars in fossil

malacostraca Malacostraca (from New Latin; ) is the largest of the six classes of crustaceans, containing about 40,000 living species, divided among 16 orders. Its members, the malacostracans, display a great diversity of body forms and include crabs, lobs ...

n specimens is compiled by Klompmaker ''et al.'' (2019). * A three-dimensionally preserved

tanaidacea The crustacean order Tanaidacea (known as tanaids) make up a minor group within the class Malacostraca. There are about 940 species in this order. Description Tanaids are small, shrimp-like creatures ranging from in adult size, with most speci ...

n specimen belonging or related to the species '' Jurapseudes friedericianus'' is described from the

Middle Jurassic The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations ...

(

Callovian In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 166.1 ± 4.0 Ma (million years ago) and 163.5 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the ...

)

Ornatenton Formation The Ornatenton Formation is a Jurassic marine formation in Germany that is middle Callovian in age. The formation represents a shallow marine environment.Rauhut, Oliver W.M., Hübner, Tom R., and Lanser, Klaus-Peter, 2016, "A new megalosaurid the ...

(

Germany Germany, officially the Federal Republic of Germany (FRG),, is a country in Central Europe. It is the most populous member state of the European Union. Germany lies between the Baltic and North Sea to the north and the Alps to the sou ...

) by Schädel ''et al.'' (2019). * A study on the evolutionary history of

decapod Decapod may refer to: Biology * Decapoda, an order of crustaceans such as lobsters and crabs * Decapodiformes, ten-limbed cephalopods with eight arms and two tentacles Trains * 2-10-0, a steam locomotive wheel arrangement known as "Decapod" in th ...

crustaceans is published by Wolfe ''et al.'' (2019). * A study on the chemical composition of two specimens of fossilized shrimps from the Cretaceous Romualdo and Ipubi formations (Araripe Basin,

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

), and on its implications for inferring the course of the processes of fossilization of these crustaceans, is published by Barros ''et al.'' (2019). * A study on the

palaeoenvironment of La Voulte (

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...

), as indicated by data from exceptionally preserved eyes of the

polychelida Polychelida is an infraorder of decapod crustaceans. Fossil representatives are known dating from as far back as the Upper Triassic. A total of 38 extant species, all in the family Polychelidae, and 55 fossil species have been described. Histo ...

n lobster '' Voulteryon parvulus'' and from

epibiont An epibiont (from the Ancient Greek meaning "living on top of") is an organism that lives on the surface of another living organism, called the basibiont ("living underneath"). The interaction between the two organisms is called epibiosis. An epi ...

brachiopod Brachiopods (), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, ...

s associated with ''V. parvulus'', is published by Audo ''et al.'' (2019). * A study on the anatomy of the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

specimen of a putative

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pal ...

shark ''Platyacrodus unicus'' is published by Bogan, Agnolin & Ezcurra (2019), who reinterpret this specimen as a

carapace A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the und ...

of a small retroplumid crab belonging to the genus '' Costacopluma''. * An

achelata The Achelata is an infra-order of the decapod crustaceans, holding the spiny lobsters, slipper lobsters and their fossil relatives. Description The name "Achelata" derives from the fact that all the members of this group lack the chelae (claws) ...

n larval fossil with an intermediate type of morphology, interpreted as the oldest occurrence of an achelatan lobster larva reported so far, is described from the

Toarcian The Toarcian is, in the ICS' geologic timescale, an age and stage in the Early or Lower Jurassic. It spans the time between 182.7 Ma (million years ago) and 174.1 Ma. It follows the Pliensbachian and is followed by the Aalenian. The Toarc ...

Posidonia Shale The Posidonia Shale (german: Posidonienschiefer, also called Schistes Bitumineux in Luxembourg) geologically known as the Sachrang Formation, is an Early Jurassic (Toarcian) geological formation of southwestern and northeast Germany, northern Swi ...

(

) by Haug, Haug & Schweigert (2019). * Redescription of the

isopod Isopoda is an order of crustaceans that includes woodlice and their relatives. Isopods live in the sea, in fresh water, or on land. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, an ...

species '' Palaega sismondai'' Ristori (1891) is published by Hyžný, Pasini & Garassino (2019), who transfer this species to the genus ''

Bathynomus A giant isopod is any of the almost 20 species of large isopods, crustaceans distantly related to shrimp and crabs, which are decapods, in the genus ''Bathynomus''. They are abundant in the cold, deep waters of the Atlantic, Pacific, and Indian ...

''. * A

moult In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...

of a giant isopod is described from the early

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

Ranzano Formation by Pasini & Garassino (2019), representing the oldest fossil record of the genus ''Bathynomus'' from

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

. * A study on the Late Devonian ostracods from the Yangdi and Nandong sections in South China, and on their responses to the Frasnian-Famennian event, is published by Song, Huang & Gong (2019). * A diverse earliest Triassic ostracod fauna is reported from the Yangou section in South China by Qiu ''et al.'' (2019). * A revision of ostracods from the Upper

to Lower

Miocene The Miocene ( ) is the first 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 means "less recent" ...

Pirabas Formation (

) is published by Nogueira, Ramos & Hunt (2019). * A study on changes of diversity of

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago (Mya) to the beginning of the present Quaternary Period Mya. ...

fossil marine ostracods from

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mo ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

is published by Shin ''et al.'' (2019). * A study on deep-sea

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

ostracod assemblages from the southern

Sea of Japan The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it h ...

covering the last 2 million years, evaluating their responses to the

Mid-Brunhes Event The Mid-Brunhes Event (MBE) is a climatic shift evident in a number of marine sediment and Antarctic ice cores. It corresponds to an increase in amplitude of glacial-interglacial cycles.EPICA community members (2004) Nature, 365, 143-147. The MBE ...

, orbital-scale climatic cycles, and fluctuations of the Tsushima Warm Current, is published by Huang ''et al.'' (2019). * A three-dimensionally preserved specimen of a late growth stage of the phosphatocopid species '' Cyclotron angelini'' is described from the

Furongian The Furongian is the fourth and final epoch and series of the Cambrian. It lasted from to million years ago. It succeeds the Miaolingian series of the Cambrian and precedes the Lower Ordovician Tremadocian Stage. It is subdivided into thre ...

strata of northern

Poland Poland, officially the Republic of Poland, , is a country in Central Europe. Poland is divided into Voivodeships of Poland, sixteen voivodeships and is the fifth most populous member state of the European Union (EU), with over 38 mill ...

by Olempska ''et al.'' (2019). * A study on the ecology of

clam shrimp Clam shrimp are a group of bivalved branchiopod crustaceans that resemble the unrelated bivalved molluscs. They are extant and also known from the fossil record, from at least the Devonian period and perhaps before. They were originally classifi ...

s from the Anjiagou and Hengdaozi beds of the

Lower Cretaceous Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Gloucestershire, England See also *Nizhny Nizhny (russian: Ни́жний; masculine), Nizhnyaya (; feminine), or Nizhneye (russian: Ни́� ...

Yixian Formation The Yixian Formation (; formerly transcribed as Yihsien Formation) is a geological formation in Jinzhou, Liaoning, People's Republic of China, that spans the late Barremian and early Aptian stages of the Early Cretaceous. It is known for its ...

( China) is published by Hethke ''et al.'' (2019). * A study on the oxygen isotope composition of

whale barnacle Whale barnacles are species of acorn barnacle that belong to the family Coronulidae. They typically attach to baleen whales, and sometimes settle on toothed whales. The whale barnacles diverged from the turtle barnacles about three million year ...

shells from three

Pleistocene The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed ...

localities along the eastern Pacific coast, and on their implications for the knowledge of the history of whale migrations, is published by Taylor ''et al.'' (2019). * A study on the internal soft-tissue anatomy of '' Hesslandona angustata'' is published by Liu ''et al.'' (2019).

New taxa

Malacostracans

Ostracods

Other crustaceans

Insects

Trilobites

Research

* A study on the rates of evolution of trilobites in the

Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ag ...

is published by Paterson, Edgecombe & Lee (2019), who interpret their findings as indicative of Cambrian rather than

Precambrian The Precambrian (or Pre-Cambrian, sometimes abbreviated pꞒ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of th ...

origin of trilobites, and as indicating that the Cambrian explosion had already largely concluded by the time the typical Cambrian fossil record begins (≈521 Ma). * A study on repaired injuries in trilobite specimens from the Cambrian Ruin Wash

Lagerstätte A Lagerstätte (, from ''Lager'' 'storage, lair' '' Stätte'' 'place'; plural ''Lagerstätten'') is a sedimentary deposit that exhibits extraordinary fossils with exceptional preservation—sometimes including preserved soft tissues. These for ...

(

Nevada Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

) is published by Pates & Bicknell (2019), who interpret their findings as indicative of species specific predation on Cambrian trilobites, and of enlarged spines in some trilobite species serving as possible predation deterrents. * A study on the morphology and

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 egg to adult. The term can also be used to refer to the stu ...

of ''

Changaspis ''Changaspis'' is an extinct genus of trilobite that lived during the lower Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted ...

elongata'', based on data from specimens from the Lazizhai section of the Balang Formation (Cambrian Stage 4;

Guizhou Guizhou (; formerly Kweichow) is a landlocked province in the southwest region of the People's Republic of China. Its capital and largest city is Guiyang, in the center of the province. Guizhou borders the autonomous region of Guangxi to t ...

, China), is published by Du ''et al.'' (2019). * A cluster of over 100 juvenile trilobites belonging to the genus '' Aphelaspis'' is reported from the Cambrian (

Paibian The Paibian is the lowest stage of Furongian series of the Cambrian. It follows the Guzhangian ( 3rd series of the Cambrian) and is succeeded by the Jiangshanian Stage. The base is defined as the first appearance of the trilobite ''Glyptagnostus ...

) Conasauga Formation (

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to t ...

, United States) by Schwimmer & Montante (2019). * A study on patterns of occupancy and diversity trajectories in late Cambrian-early

Ordovician The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. ...

trilobite communities from the

Argentine Argentines (mistakenly translated Argentineans in the past; in Spanish ( masculine) or ( feminine)) are people identified with the country of Argentina. This connection may be residential, legal, historical or cultural. For most Argentines ...

Cordillera Oriental is published by Serra, Balseiro & Waisfeld (2019). * A study on the phylogenetic relationships of members of the family

Olenidae Olenidae is a family of ptychopariid trilobites. Some genera, '' Balnibarbi'' and '' Cloacaspis'', are thought to have evolved a symbiotic relationship with sulfur-eating bacteria from which they derived nutrition. Genera * Acerocare * Acer ...

is published by Monti & Confalonieri (2019). * A study on the phylogenetic relationships of members of the olenid subfamily Balnibarbiinae is published by Hopkins (2019). * Nine specimens of '' Symphysurus ebbestadi'' preserving all key stages of the

exoskeleton An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton ( endoskeleton) in for example, a human. In usage, some of the ...

moulting In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...

process are described from the Lower Ordovician

Fezouata Formation The Fezouata Formation or Fezouata Shale is a geological formation in Morocco which dates to the Early Ordovician.

(

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria ...

) by Drage ''et al.'' (2019). * A study on clusters of ''

Ampyx priscus ''Ampyx'' is an Ordovician-Silurian genus of Asaphid trilobites of the family Raphiophoridae. Species of ''Ampyx'' are characterized by three extended spines on the head-shield, one spine derived from each free cheek, and one spine emanati ...

'' from the Ordovician Fezouata Shale of Morocco is published by Vannier ''et al.'' (2019), who interpret these clusters as evidence of a collective behaviour rather than a result of passive transportation and accumulation. * A study on the phylogenetic relationships of the species and subspecies assigned to the

phacopid Phacopidae is a family of phacopid trilobites that ranges from the Lower Ordovician to the Upper Devonian, with representatives in all paleocontinents. Description As in all Phacopina, the eyes (if present) consist of very large (0.5 mm in ' ...

genus '' Austerops'' is published by Oudot ''et al.'' (2019). * A study on the morphological changes in the

of the Ordovician phacopid trilobite ''

Calyptaulax ''Calyptaulax'' (Cooper, 1930) is a genus of trilobites in the order Phacopida that existed during the middle and upper Ordovician in what is now the U.S. states of New York, Oklahoma, Illinois, Missouri, Virginia, Vermont, Nevada, Iowa, Wisconsin ...

strasburgensis'' is published by Jacobs & Carlucci (2019). * A well-preserved body cluster of 18 specimens of ''

Arctinurus ''Arctinurus boltoni'' is a large (up to 30 cm) lichid trilobite of the mid-Silurian. This trilobite reached about eight inches in length, though the normal adult carapace was about four inches. It lived in moderately deep-water in semi-tr ...

boltoni'' is described from the

Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago (Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoi ...

Rochester Shale The Rochester Shale is a geologic formation exposed in New York and West Virginia. It preserves fossils dating back to the Silurian period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation ...

(

New York New York most commonly refers to: * New York City, the most populous city in the United States, located in the state of New York * New York (state), a state in the northeastern United States New York may also refer to: Film and television * '' ...

) by Bicknell, Paterson & Hopkins (2019). * A study on development and evolution of the

cephalon Cephalon, Inc. was an American biopharmaceutical company co-founded in 1987 by pharmacologist Frank Baldino, Jr., neuroscientist Michael Lewis, and organic chemist James C. Kauer—all three former scientists with the DuPont Company. Baldino ...

and the

pygidium The pygidium (plural pygidia) is the posterior body part or shield of crustaceans and some other arthropods, such as insects and the extinct trilobites. In groups other than insects, it contains the anus and, in females, the ovipositor. It is com ...

in phacopid trilobites is published by Oudot ''et al.'' (2019). * A study on the internal structures of eyes of trilobites belonging to the genera ''

Asaphus ''Asaphus'' () is a genus of trilobites that is known from the Lower (upper Arenig) and Middle Ordovician of northwestern Europe (Sweden, Estonia, Saint Petersburg Area). Etymology The generic name is derived from the Greek word ''asaphes'', ...

'' and '' Archegonus'' is published by Scholtz, Staude & Dunlop (2019); the study is subsequently criticized by Schoenemann & Clarkson (2021). * A study on the variability of trilobite

behaviour is published by Drage (2019).

New taxa

Other arthropods

Research

* A study on the

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

of appendages of the euarthropod ''

Ercaicunia ''Ercaicunia'' is genus of bivalved Cambrian arthropod from the Chengjiang biota of Yunnan, China. It contains a single species, ''E. multinodosa'' that was described by Luo et al. in 1999. The total length of the body ranges from . The bivalved ...

multinodosa'' from the Early

Chengjiang biota The Maotianshan Shales are a series of Early Cambrian deposits in the Chiungchussu Formation, famous for their '' Konservat Lagerstätten'', deposits known for the exceptional preservation of fossilized organisms or traces. The Maotianshan Shales ...

( China) is published by Zhai ''et al.'' (2019). * Description of the appendicular morphology of ''

Sinoburius ''Sinoburius'' is an extinct genus of xandarellid artiopodan known from the Cambrian aged Chengjiang Biota The Maotianshan Shales are a series of Early Cambrian deposits in the Chiungchussu Formation, famous for their '' Konservat Lagerstätt ...

lunaris'' is published by Chen ''et al.'' (2019). * Description of a new specimen of ''

Emeraldella ''Emeraldella'' is a genus of arthropod known from the Middle Cambrian of North America. The type species ''E. brocki'' was described in 1912 from the Burgess Shale. 21 specimens of ''Emeraldella'' are known from the Greater Phyllopod bed, where ...

brutoni'' from the Cambrian

Wheeler Formation The Wheeler Shale (named by Charles Walcott) is a Cambrian ( 507 Ma) fossil locality world-famous for prolific agnostid and ''Elrathia kingii'' trilobite remains (even though many areas are barren of fossils) and represents a Konzent ...

( Drum Mountains,

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

), providing new information on the appendicular anatomy of this species, is published by Lerosey-Aubril & Ortega-Hernández (2019). * Description of new bradoriid fossils from the Chengjiang biota, revealing hitherto unknown morphological differences in limb anatomy between bradoriid species, is published by Zhai ''et al.'' (2019), who evaluate the implications of this finding for the knowledge of the phylogenetic relationships of bradoriids. * A study on the appendage structure of ''

Naraoia ''Naraoia'' is a genus of small to average size (about 2-4½ cm long) marine arthropods within the family Naraoiidae, that lived from the early Cambrian to the late Silurian period. The species are characterized by a large alimentary system and s ...

spinosa'' at both juvenile and adult stages is published by Zhai ''et al.'' (2019). * Description of exceptionally preserved soft tissues from mature individuals of ''

Peronopsis ''Peronopsis'' (meaning "broach-like" or possibly "boot-like") is a genus of trilobite restricted to the Middle Cambrian. Its remains have been found in Asia, Australia, Europe, and North America. Etymology The subgenus ''Svenax'' is a cont ...

'' and ''

Ptychagnostus ''Ptychagnostus'' is a member of the agnostida that lived during the Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 mi ...

'' from the Cambrian

Burgess Shale The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At old (middle Cambrian), it is one of the earliest fos ...

(

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost Provinces and territories of Canada, province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include ...

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tota ...

), and a study on their implications for inferring the phylogenetic placement of agnostinids within Arthropoda, is published by Moysiuk &

Caron A caron (), háček or haček (, or ; plural ''háčeks'' or ''háčky'') also known as a hachek, wedge, check, kvačica, strešica, mäkčeň, varnelė, inverted circumflex, inverted hat, flying bird, inverted chevron, is a diacritic mark (� ...

(2019). * Completely enrolled,

phosphatized Phosphatic fossilization has occurred in unusual circumstances to preserve some extremely high-resolution microfossils in which careful preparation can even reveal preserved cellular structures. Such microscopic fossils are only visible under the ...

specimens of ''

Tsunyidiscus ''Tsunyidiscus'' is a trilobite belonging to the Suborder Eodiscina. ''Tsunyidiscus'' appeared near the end of the Lower Cambrian, during the late Atdabanian Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambr ...

yanjiazhaiensis'' are described from

Cambrian Stage 3 Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambrian Stage 2 and precedes Cambrian Stage 4, although neither its base nor top have been formally defined. The plan is for its lower boundary to correspond approxi ...

of South China by Dai ''et al.'' (2019). * The

ontogenetic 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 egg to adult. The term can also be used to refer to the s ...

series of ''

Pagetia ''Pagetia'' Walcott, 1916. is a small genus of trilobite, assigned to the Eodiscinid family Pagetiidae and which had global distribution during the Middle Cambrian. The genus contains 55 currently recognized species, each with limited spatial a ...

vinusta'' is documented from the Cambrian (

Wuliuan The Wuliuan stage is the fifth stage of the Cambrian, and the first stage of the Miaolingian Series of the Cambrian. It was formally defined by the ICS in 2018. Its base is defined by the first appearance of the trilobite species '' Oryctocepha ...

) Kaili Formation (

, China) by Cui ''et al.'' (2019). * A study reevaluating crystals of a copper sulfide mineral found in association with specimens of ''

Marrella ''Marrella'' is an extinct genus of marrellomorph arthropod known from the middle Cambrian Burgess Shale of British Columbia. It is the most common animal represented in the Burgess Shale, with tens of thousands of specimens collected. Much rar ...

splendens'' from the

, originally interpreted as evidence that the animal's blood contained the Cu-bearing protein

hemocyanin Hemocyanins (also spelled haemocyanins and abbreviated Hc) are proteins that transport oxygen throughout the bodies of some invertebrate animals. These metalloproteins contain two copper atoms that reversibly bind a single oxygen molecule (O2 ...

, is published by Gaines ''et al.'' (2019). * A study on the anatomy of the nervous system of ''

Alalcomenaeus ''Alalcomenaeus'' is one of the most widespread and longest-surviving arthropod genera of the Early and Middle Cambrian. Known from over 300 specimens in the Burgess Shale and the Chengjiang biota. it is a member of the group Megacheira. Morphol ...

'' is published by Ortega-Hernández, Lerosey-Aubril & Pates (2019). * Juvenile specimens of

stylonurine Stylonurina is one of two suborders of eurypterids, a group of extinct arthropods commonly known as "sea scorpions". Members of the suborder are collectively and informally known as "stylonurine eurypterids" or "stylonurines". They are known fro ...

eurypterid Eurypterids, often informally called sea scorpions, are a group of extinct arthropods that form the order Eurypterida. The earliest known eurypterids date to the Darriwilian stage of the Ordovician period 467.3 million years ago. The group is ...

s belonging to the family

Hardieopteridae The Hardieopteridae are a family of eurypterids, an extinct group of chelicerate arthropods commonly known as "sea scorpions". The family is one of two families contained in the superfamily Kokomopteroidea (along with Kokomopteridae), which in t ...

are described from the

Famennian The Famennian is the latter of two faunal stages in the Late Devonian Epoch. The most recent estimate for its duration estimates that it lasted from around 371.1 million years ago to 359.3 million years ago. An earlier 2012 estimate, still used ...

locality of Strud (

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to ...

) by Lamsdell ''et al.'' (2019), who interpret their findings as evidence indicating that eurypterids underwent a marine to freshwater transition during the

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, w ...

, and that juvenile eurypterids inhabited sheltered nursery pools (and migrated to rivers upon reaching maturity). * A study on the structure of the eyes of eurypterids is published by Schoenemann, Poschmann & Clarkson (2019). * A study on ontogenetic changes in

prosoma The cephalothorax, also called prosoma in some groups, is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. (The terms ''prosoma'' and ''opisthosoma'' are equivalent to ''ce ...

l morphology in Carboniferous horseshoe crab ''

Euproops ''Euproops'' Meek, 1867, is an extinct genus of xiphosuran, related to the modern horseshoe crab. It lived during the Carboniferous Period. The '' Treatise on Invertebrate Paleontology'' describes ''Euproopidae'' as "small forms with wedge-sh ...

danae'' is published by Tashman, Feldmann & Schweitzer (2019). * A study on the anatomy of the appendages of the Cretaceous xiphosurid ''

Tachypleus syriacus ''Tachypleus'' is a genus of south, southeast The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal dir ...

'' and on the evolution of fossil horseshoe crab appendages is published by Bicknell ''et al.'' (2019). * A study re-evaluating the fossil evidence for lateral compound eyes in

Paleozoic The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ' ...

horseshoe crabs is published by Bicknell, Amati & Ortega-Hernández (2019). * A study on the morphology of the millipede ''

Phryssonotus ''Phryssonotus'' is a genus of bristle millipedes containing around nine extant species. Species are characterized by the possession of dark, rear-projecting scale-shaped bristles (trichomes) on the tergites; all other bristles are long and hai ...

burmiticus'' from the Cretaceous amber from

Myanmar Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...

is published by Su, Cai & Huang (2019).

New taxa

References

{{Reflist, 2 2019 in paleontology