Ischioceratops

Ischioceratops; Temporal range: 69 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
	Holotype
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	†Ornithischia
Clade:	†Ceratopsia
Family:	†Leptoceratopsidae
Genus:	†Ischioceratops
Species:	†I. zhuchengensis
Binomial name
	†Ischioceratops zhuchengensis; He et al., 2015

Ischioceratops (lit. 'ischium-horned face') is an

Period in what is now China

.

Ischioceratops was a small sized, moderately-built, ground-dwelling,

quadrupedal herbivore, whose total body length has been estimated to be about 2 m (6.6 ft). The ceratopsians were a group of dinosaurs with parrot-like beaks which fed on vegetation and thrived in North America and Asia during the Cretaceous Period, which ended approximately 66 million years ago, at which point they all became extinct. Its name means "ischium horned face", referring to the peculiar shape of the ischiatic bones.^[1]

Ischioceratops existed in the Wangshi Group during the late Cretaceous. It lived alongside centrosaurines, saurolophines, and tyrannosaurines. The most common creatures in the formation were Sinoceratops and Zhuchengtyrannus.

Discovery and naming

In 2015, the

Life Science Identifiers were required for its validity. These were 19A423ED-8EAA -4842-9ECF-695876EC5EC0 for the genus and 71CD0FAE-070C-4CC4-96CC-B37D5B1071CE for the species.^[1] Ischioceratops was one of eighteen dinosaur taxa from 2015 to be described in open access or free-to-read journals.^[2]

The

vertebrae in an articulated series, and the right femur, tibia and fibula.^[1]

Description

Size and distinguishing traits

Ischioceratops was a relatively small ceratopsian, reaching 2 m (6.6 ft) in length. The describing authors indicated some distinguishing traits. The taxon has been referred to Leptoceratopsidae and is distinguished from other known leptoceratopsids based on the following combination of characters: nine sacral vertebrae, more than in any other known basal (non-ceratopsid) ceratopsian but fewer than in ceratopsids; the ischium has a robust shaft that resembles that of a recurved bow and flares gradually to form a subrectangular-shaped obturator process in its middle portion while an elliptical fenestra perforates the obturator process. This morphology, unique for the Dinosauria as a whole, was seen as a single autapomorphy, unique derived character.^[1]

Skeleton

Ischioceratops is one of the few ceratopsian dinosaurs which is not known by the skull. The most peculiar traits are located in the ischium. With most relatives the ischium shaft has a constant curvature to the rear. Another characteristic of Ischioceratops is the presence of an elevation in the proximal part of its tail, which is present also in Protoceratops, Koreaceratops and in a more similar way in Montanoceratops and Cerasinops. The elevation forms a tail crest.