''Ojoraptorsaurus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

oviraptorosaurian 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 ...

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

from the

late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger 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 ''creta'', the ...

. ''Ojoraptorsaurus'' is only known from pubic bones found at the Naashoibito Member of the

Ojo Alamo Formation The Ojo Alamo Formation is a geologic formation in New Mexico spanning the Mesozoic/Cenozoic boundary. Non-avian dinosaur fossils have controversially been identified in beds of this formation dating from after the Cretaceous–Paleogene extinctio ...

dating to the early

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ...

, about 69 million years ago. It was first named by Robert M. Sullivan, Steven E. Jasinski and Mark P.A. van Tomme in

2011 File:2011 Events Collage.png, From top left, clockwise: a protester partaking in Occupy Wall Street heralds the beginning of the Occupy movement; protests against Libyan dictator Muammar Gaddafi, who was killed that October; a young man celebrate ...

and the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

is ''Ojoraptorsaurus boerei''. The generic name combines a reference to the formation with a

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''raptor'', "plunderer", and a Latinised Greek ''saurus'', "lizard". The specific name honours

oceanographer Oceanography (), also known as oceanology and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics ...

Arjan Boeré who found the specimen.

Description

Ojoraptorsaurus boerei profile reconstruction

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 several ...

of ''Ojoraptorsaurus'' is SMP VP-1458, an incomplete pair of fused pubes. Due to the fusion of the pubes, this specimen is believed to have been a mature individual. Most caenagnathid species are known from very few remains, and ''Ojoraptorsaurus'' is no exception. The holotype was compared to well-described pubic remains of other oviraptorosaurians, namely ''

Microvenator ''Microvenator'' (meaning "small hunter") is a genus of dinosaur from the Early Cretaceous Cloverly Formation in what is now south central Montana. ''Microvenator'' was an oviraptorosaurian theropod. The holotype fossil is an incomplete skeleton ...

'', ''

Epichirostenotes ''Epichirostenotes'' (meaning "above ''Chirostenotes''", because it lived after the latter genus) is a genus of oviraptorosaurian dinosaur from the late Cretaceous. ''Epichirostenotes'' is known from an incomplete skeleton found in 1923 at the ...

'', ''

Nomingia ''Nomingia'' is a genus of oviraptorid theropod dinosaur hailing from the Late Cretaceous Bugin Tsav Beds of Mongolia. Discovery and naming The remains, consisting of most of the vertebral column, pelvic girdle and left tibio-tarsus, holotyp ...

'', and CM 78001 (now known as ''

Anzu Anzu may refer to: *Anzû, a divine storm-bird in several Ancient Mesopotamian religion, Mesopotamian religions *Anzu (dinosaur), ''Anzu'' (dinosaur), a genus of theropod dinosaur containing the species ''Anzu wyliei'' As a given name is a Japan ...

''). It shares with the latter three taxa an enclosed fossa on the inside edge of the pubis near the

acetabular The acetabulum (), also called the cotyloid cavity, is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint. Structure There are three bones of the ''os coxae'' (hip bone) that ...

rim, a trait which may be diagnostic to caenagnathids (in which case ''Nomingia'' is a caenagnathid). ''Ojoraptorsaurus's'' fossa is further away from the acetabular rim than those of the other species, a feature characteristic to the genus. Among compared oviraptorosaurians, ''Ojoraptorsaurus'' is most similar to ''Epichirostenotes'', a genus differentiated from ''

Chirostenotes ''Chirostenotes'' ( ; named from Greek 'narrow-handed') is a genus of oviraptorosaurian dinosaur from the late Cretaceous (about 76.5 million years ago) of Alberta, Canada. The type species is ''Chirostenotes pergracilis''. History of discovery ...

'' in the same paper that ''Ojoraptorsarus'' was described in. By comparing pubic proportions with those of CM 78001 (''Anzu''), ''Ojoraptorsaurus'' has been estimated to have been about 1.8 to 2.1 meters (5.9 to 6.9 feet) in length, about 20% smaller than ''Epichirostenotes''. ''Ojoraptorsaurus'' differs from other caenagnathids due to possessing the following

autapomorphies In phylogenetics, an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa, not even those most closely related to t ...

: * A “spoon-shaped” depression on the anterior dorsal surface of the pubic boot. * An enclosed fossa on the inside edge of the pubis which lies 1 centimeter away from the acetabular rim. * The portion of the pubic shaft directly above the pubic boot being slightly anteriorly convex. * A sub-trapezoidal iliac peduncle articular surface of the pubis.

References

Caenagnathids Late Cretaceous dinosaurs of North America Fossil taxa described in 2011 Paleontology in New Mexico Ojo Alamo Formation Maastrichtian genus first appearances Maastrichtian genus extinctions {{theropod-stub

Description

See also

References