''Aralosaurus'' was a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

hadrosaurid Hadrosaurids (), also hadrosaurs or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod fami ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

that lived during the

Late 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 ''cre ...

in what is now

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 ...

. It is known only by a posterior half of a skull (devoid of its mandible) and some post-cranial bones found in the

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 ...

in rocks dated from the Upper

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 ...

-Lower

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 ...

boundary, at about 83.6 Ma (millions of years). Only one

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

is known, ''Aralosaurus tuberiferus'', described by

Anatoly Konstantinovich Rozhdestvensky Anatoly Konstantinovich Rozhdestvensky (, 1920–1983) was a Soviet paleontologist responsible for naming many dinosaurs, including '' Aralosaurus'' and '' Probactrosaurus''. References Soviet paleontologists 1920 births 1983 deaths Russi ...

in 1968. The genus name means

Aral Sea The Aral Sea () was an endorheic lake lying between Kazakhstan to its north and Uzbekistan to its south, which began shrinking in the 1960s and had largely dried up into desert by the 2010s. It was in the Aktobe and Kyzylorda regions of Kazakhst ...

lizard, because it was found to the northeast of the Aral Sea. The specific epithet ''tuberiferus'' means bearing a tuber because the posterior part of the

nasal bone The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose. Eac ...

rises sharply in front of the

orbits In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an physical body, object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an satellite, artificia ...

like an outgrowth. ''Aralosaurus'' was originally reconstituted with a nasal arch similar to that of North American ''

Kritosaurus ''Kritosaurus'' is an incompletely known genus of hadrosaurid (duck-billed) dinosaur. It lived about 74.5-66 million years ago, in the Late Cretaceous of North America. The name means "separated lizard" (referring to the arrangement of the cheek ...

'' (a comparison based on a specimen now placed in the genus ''

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 ...

''). For many years, ''Aralosaurus'' was thus placed in the clade of the

Hadrosaurinae Hadrosaurids (), also hadrosaurs or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod fami ...

. This classification was invalidated in 2004, following the re-examination of the skull of the animal which allowed to identify in ''Aralosaurus'' many typical characters of

Lambeosaurinae Lambeosauridae /ˌlæmbiəˈsɔːraɪniː/ (meaning 'lambe's lizards') is an extinct group of crested hadrosauroid dinosaurs. Description Size Uncertainty surrounds the size of lambeosaurs from the European continent. Hadrosaurs found there, ...

. In particular, this study revealed that ''Aralosaurus'' had a hollow bony structure located far in front of the orbits, which communicated with the

respiratory tract The respiratory tract is the subdivision of the respiratory system involved with the process of conducting air to the alveoli for the purposes of gas exchange in mammals. The respiratory tract is lined with respiratory epithelium as respirato ...

. This structure being broken at its base, its shape and size remains undetermined. More recently, ''Aralosaurus'' has been identified as the most basal Lambeosaurinae, and placed with its close relative ''

Canardia ''Canardia'' is an extinct genus of lambeosaurine dinosaur known from the Late Cretaceous Marnes d'Auzas Formation (late Maastrichtian stage) of Haute-Garonne Departments of France, department, in Occitania (administrative region), Occitanie Regi ...

'' from the upper

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 ...

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 ...

in the new clade of

Aralosaurini Lambeosauridae Help:IPA/English, /ˌlæmbiəˈsɔːraɪniː/ (meaning 'lambe's lizards') is an extinct group of crested hadrosauroid dinosaurs. Description Size Uncertainty surrounds the size of lambeosaurs from the European continent. Hadrosau ...

Discovery

The partial

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

of ''Aralosaurus'' was discovered in 1957 near the Shakh-Shakh locality during a

Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

expedition in central Kazakhstan (which at the time was part of the

USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

). In addition to the skull (which lacks most of the

snout A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. In many animals, the structure is called a muzzle, Rostrum (anatomy), rostrum, beak or proboscis. The wet furless surface around the nostrils of the n ...

and the entire

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

), the material also included isolated

teeth A tooth (: teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...

and postcranial elements most often fragmentary (

ulna The ulna or ulnar bone (: ulnae or ulnas) is a long bone in the forearm stretching from the elbow to the wrist. It is on the same side of the forearm as the little finger, running parallel to the Radius (bone), radius, the forearm's other long ...

radius In classical geometry, a radius (: radii or radiuses) of a circle or sphere is any of the line segments from its Centre (geometry), center to its perimeter, and in more modern usage, it is also their length. The radius of a regular polygon is th ...

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 ...

tibia The tibia (; : tibiae or tibias), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two Leg bones, bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outsi ...

fibula The fibula (: fibulae or fibulas) or calf bone is a leg bone on the lateral side of the tibia, to which it is connected above and below. It is the smaller of the two bones and, in proportion to its length, the most slender of all the long bones. ...

astragalus Astragalus may refer to: * ''Astragalus'' (plant), a large genus of herbs and small shrubs *Astragalus (bone) The talus (; Latin for ankle or ankle bone; : tali), talus bone, astragalus (), or ankle bone is one of the group of foot bones known ...

metatarsals 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 nu ...

). The only complete elements were a

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 ...

and a metatarsal. It is only in 1968 that Rozhdestvensky described and named the animal. He estimated the size of the skull at about 65 cm and the size of the animal at about 6.5 m long. As the cranial sutures are far from fusioned, this specimen was probably immature. At the time, Rozhdestvensky argued that the skull of ''Aralosaurus'' presented the greatest resemblance with the skull of ''

'' with the presence of a nasal arch in front of the

(the comparisons were based with specimens attributed today to ''

'', not to ''Kritosaurus''). So, the animal was classified among the

, which are hadrosaurs devoid of cranial crest or with a solid bony crest. In 2004, the skull of ''Aralosaurus'' was re-examined by Godefroit and colleagues, and according to them, the bone fragments identified by Rozhdestvensky as the middle part of the nasal arch and the posterior portion of the

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammals h ...

seem to have been lost. These fragments were originally found isolated while the rest of the skull was articulated (including a posterior fragment of the nasal). So that it is no longer possible today to confirm the presence of a nasal arch in ''Aralosaurus''. On the other hand, this study shows that ''Aralosaurus'' was not a gryposaur-like hadrosaurine, because the purported nasal boss was in fact a fragment of a hollow structure. Indeed, Godefroit and colleagues did not find any hadrosaurine diagnostic characters in ''Aralosaurus''. On the contrary, the skull of ''Aralosaurus'' presents several features (in the

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

, parietal,

squamosal The squamosal is a skull bone found in most reptiles, amphibians, and birds. In fishes, it is also called the pterotic bone. In most tetrapods, the squamosal and quadratojugal bones form the cheek series of the skull. The bone forms an ancestra ...

and especially the

nasal Nasal is an adjective referring to the nose, part of human or animal anatomy. It may also be shorthand for the following uses in combination: * With reference to the human nose: ** Nasal administration, a method of pharmaceutical drug delivery * ...

) which indicates its inclusion among the

. Notably, the posterior fragment of the nasal, which is clearly articulated to the rest of the skull, rises just in front of the orbits and forming or participating to a hollow crest-like structure. As this structure is broken at its base, it is not possible to deduce its size and shape. However, in rostral view, the nasal is clearly hollow, it is deeply excavated rostrally by a broad groove that communicates directly with the ventral side of the posterior part of the bone. It is therefore clear that in ''Aralosaurus'' the nasal crest surrounded part of the

respiratory system The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and plants. The anatomy and physiology that make this happen varies grea ...

. The extension of the nasal cavity inside a hollow crest is typically a lambeosaurine feature, thus confirming the inclusion of ''Aralosaurus'' among them. ''Aralosaurus'' also exhibits several cranial characters which indicate that it was a basal member of the group. Although having a hollow nasal structure, the latter was located in front of the orbits, a primitive position in lambeosaurines. In the most advanced representatives of the group, the nasal migrates to a caudodorsal position because of the important development of the

e in these forms. In addition, in more derived lambeosaurines, the skull roof is modified to form a fixation zone for the hollow crest, whereas in ''Aralosaurus'' the skull roof does not present any particular modification. The shape and the size of the crest-like structure of ''Aralosaurus'' is unknown. The fragments that were previously interpreted as a part of a gryposaur-like nasal arch and could have helped to reconstruct the circumnarial region of ''Aralosaurus'', have been lost. So, the discovery of more complete specimens is necessary for a better knowledge of the shape and the size of this hollow structure.

Classification

The following cladogram was produced by Albert Prieto-Márquez and his colleagues in 2013, it shows the phylogeny of

. ''Aralosaurus'' is closely related to ''Canardia'' and both genera are included in the tribe of

, which are identified as the most basal members of Lambeosaurinae.

Paleobiogeography

''Aralosaurus'' lived about 20 million years before its close relative ''Canardia''. The latter inhabited the Ibero-Armorican Island, which was the westernmost island of the Late Cretaceous

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

Archipelago An archipelago ( ), sometimes called an island group or island chain, is a chain, cluster, or collection of islands. An archipelago may be in an ocean, a sea, or a smaller body of water. Example archipelagos include the Aegean Islands (the o ...

. As no lambeosaurines were known in the rich localities of late

and early

ages of the Ibero-Armorican Island, it was suggested that the descendants of ''Aralosaurus'' had to reach this island rather late, perhaps at the end of the early Maastrichtian or during the late Maastrichtian. The discovery later in Spain of numerous lambeosaurines remains in the highest levels of the lower Maastrichtian argues for the first hypothesis. This

migration Migration, migratory, or migrate may refer to: Human migration * Human migration, physical movement by humans from one region to another ** International migration, when peoples cross state boundaries and stay in the host state for some minimum le ...

was probably carried out in several stages, firstly by temporary terrestrial links between the landmass of Western Asia and the eastern islands of the European archipelago, then between the different European islands up to the Ibero-Armorican Island. ''Canardia'' was a rather archaic form for its time and the Ibero-Armorican Island was perhaps an ultimate refuge for the

Paleoecology

The

sediment Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...

s of the Bostobe Formation consist mainly of

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impuriti ...

s and

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

s, and correspond to

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high Discharge (hydrolog ...

and

estuarine An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

environments in a

subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Ge ...

tropical climate Tropical climate is the first of the five major climate groups in the Köppen climate classification identified with the letter A. Tropical climates are defined by a monthly average temperature of or higher in the coolest month, featuring hot te ...

. These different

biotope A biotope is an area of uniform environmental conditions providing a living place for a specific assemblage of flora (plants), plants and fauna (animals), animals. ''Biotope'' is almost synonymous with the term habitat (ecology), "habitat", which ...

s were located on the west coast of the

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

n continent of the time, on the edge of the ancient

Turgai Sea The Turgai Strait, also known as the Turgay/Turgai Sea, Obik Sea, Ural Sea or West Siberian Sea, was a large shallow body of salt water (an epicontinental or epeiric sea) during the Mesozoic through Cenozoic Eras. It extended north of the presen ...

which connected the Tethys to the

Arctic Ocean The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, ...

. The shallow marine waters west of this fluvial coastal plain were the site of intense organic productivity due to

upwelling Upwelling is an physical oceanography, oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface. It replaces the warmer and usually nutrient-depleted sur ...

conditions caused by strong winds from the mainland. These winds were also the cause of a significant

aridification Aridification is the process of a region becoming increasingly arid, or dry. It refers to long term change, rather than seasonal variation. It is often measured as the reduction of average soil moisture content. It can be caused by reduced preci ...

of the climate in this region during the Santonian and early Campanian, causing a change in the

flora Flora (: floras or florae) is all the plant life present in a particular region or time, generally the naturally occurring (indigenous (ecology), indigenous) native plant, native plants. The corresponding term for animals is ''fauna'', and for f ...

angiosperms Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed within a fruit. T ...

, with a rarefaction of broad-leaved forms and a proliferation of small and narrow-leaved species of the family

Ulmaceae The Ulmaceae () are a family (biology), family of flowering plants that includes the elms (genus ''Ulmus''), and the zelkovas (genus ''Zelkova''). Members of the family are widely distributed throughout the Temperate, north temperate zone, and ha ...

. Angiosperms accounted for 75% of the flora of these biotopes, the rest being

conifers Conifers () are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All e ...

and rare

ginkgo ''Ginkgo'' is a genus of non-flowering seed plants, assigned to the gymnosperms. The scientific name is also used as the English common name. The order to which the genus belongs, Ginkgoales, first appeared in the Permian, , and ''Ginkgo'' is n ...

s and

cycads Cycads are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or ...

. The locality of Shakh Shakh, where ''Aralosaurus'' was found, yielded a diverse fauna including many fish (

chondrichthyans Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fish'', which have skeletons ...

, chondrosteans, and

holosteans Holostei is a group of ray-finned bony fish. It is divided into two major clades, the Halecomorphi, represented by the single living genus, '' Amia'' with two species, the bowfins (''Amia calva'' and ''Amia ocellicauda''), as well as the Ginglymo ...

), Anura, at least six species of

turtle Turtles are reptiles of the order (biology), order Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Crypt ...

s some of which had a carapace at least 75 cm long, a

scincomorph Scincomorpha is an infraorder and clade of lizards including skinks (Scincidae) and their close relatives. These include the living families Cordylidae (girdled lizards), Gerrhosauridae (plated lizards), and Xantusiidae (night lizards), as well ...

, crocodylians,

pterosaur Pterosaurs are an extinct clade of flying reptiles in the order Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 million to 66 million years ago). Pterosaurs are the earli ...

s (''

Aralazhdarcho ''Aralazhdarcho'' is a genus of azhdarchid pterosaur that lived during the Santonian to the early Campanian ages of the Late Cretaceous period in what is now Kazakhstan. The type and only known species is ''Aralazhdarcho bostobensis'', named an ...

''), birds, mammals, and several undetermined dinosaur species (

Ankylosauridae Ankylosauridae () is a family of armored dinosaurs within Ankylosauria, and is the sister group to Nodosauridae. The oldest known ankylosaurids date to around 122 million years ago and went extinct 66 million years ago during the Cretaceous–Pal ...

Sauropoda Sauropoda (), whose members are known as sauropods (; from ''wikt:sauro-, sauro-'' + ''wikt:-pod, -pod'', 'lizard-footed'), is a clade of saurischian ('lizard-hipped') dinosaurs. Sauropods had very long necks, long tails, small heads (relative t ...

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 ...

Ornithomimidae Ornithomimidae (meaning "bird-mimics") is an extinct family of theropod dinosaurs which bore a superficial resemblance to modern ostriches. Ornithomimids were fast, omnivorous or herbivorous dinosaurs known mainly from the Late Cretaceous Period ...

Therizinosauroidea Therizinosaurs (; once called segnosaurs) are an extinct group of large herbivorous theropod dinosaurs whose fossils have been mainly discovered from Cretaceous deposits in Asia and North America. Potential fragmentary remains have also been foun ...

Troodontidae 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 ...

, and

Dromaeosauridae 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 ...

). Elsewhere in this formation, the site of Akkurgan is distinguished by the presence of the two basal hadrosauroids '' Arstanosaurus'' and ''

Batyrosaurus ''Batyrosaurus'' is an extinct genus of herbivorous basal hadrosauroid dinosaur known from the Late Cretaceous Bostobe Formation (Santonian to Campanian stage) of central Kazakhstan. It contains a single species, ''Batyrosaurus rozhdestvenskyi' ...

'', as well as the pterosaur ''

Samrukia ''Samrukia'' is a genus of large Cretaceous pterosaurs known only from a single lower jaw discovered in Kazakhstan. The holotype and only known specimen was collected from the Santonian-Campanian age Bostobynskaya Formation in Kyzylorda Distri ...

'' (whose jaw was first attributed to an

Caenagnathid Caenagnathidae is a family of derived caenagnathoid dinosaurs from the Cretaceous of North America and Asia. They are a member of the Oviraptorosauria, and relatives of the Oviraptoridae. Like other oviraptorosaurs, caenagnathids had specialized ...

oviraptorosaur Oviraptorosaurs ("egg thief lizards") are a group of feathered maniraptoran dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot-like skulls, with or wi ...

, then to a giant bird), which could be a junior synonym of ''Aralazhdarcho''.

References

{{Taxonbar, from=Q132769 Lambeosaurinae Dinosaur genera Santonian dinosaurs Taxa named by Anatoly Konstantinovich Rozhdestvensky Fossil taxa described in 1968 Dinosaurs of Asia

Discovery

Classification

Paleobiogeography

Paleoecology

See also

References