Extinct genus of dinosaur from the early Jurassic of South Africa
Heterodontosaurus
Temporal range: Early Jurassic, 200–190 Ma
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Cast of specimen SAM-PK-K1332, University of California Museum of Palaeontology
Scientific classification
Domain:
Eukaryota
Kingdom:
Animalia
Phylum:
Chordata
Clade:
Dinosauria
Clade:
†Ornithischia
Family:
†Heterodontosauridae
Genus:
†Heterodontosaurus Crompton & Charig, 1962
Species:
†H. tucki
Binomial name
†Heterodontosaurus tucki
Crompton & Charig, 1962
Synonyms
Lycorhinus tucki Thulborn, 1970
Heterodontosaurus is a genus of heterodontosaurid dinosaur that lived during the Early Jurassic, 200–190 million years ago. Its only known member species, Heterodontosaurus tucki, was named in 1962 based on a skull discovered in South Africa. The genus name means "different toothed lizard", in reference to its unusual, heterodont dentition; the specific name honours G. C. Tuck, who supported the discoverers. Further specimens have since been found, including an almost complete skeleton in 1966.
Though it was a small dinosaur, Heterodontosaurus was one of the largest members of its family, reaching between 1.18 m (3 ft 10 in) and possibly 1.75 m (5 ft 9 in) in length, and weighing between 2 and 10 kg (4.4 and 22.0 lb). The skull was elongated, narrow, and triangular when viewed from the side. The front of the jaws were covered in a horny beak. It had three types of teeth; in the upper jaw, small, incisor-like teeth were followed by long, canine-like tusks. A gap divided the tusks from the chisel-like cheek-teeth. The body was short with a long tail. The five-fingered forelimbs were long and relatively robust, whereas the hind-limbs were long, slender, and had four toes.
Heterodontosaurus is the eponymous and best-known member of the family Heterodontosauridae. This family is considered a basal (or "primitive") group within the order of ornithischian dinosaurs, while their closest affinities within the group are debated. In spite of the large tusks, Heterodontosaurus is thought to have been herbivorous, or at least omnivorous. Though it was formerly thought to have been capable of quadrupedal locomotion, it is now thought to have been bipedal. Tooth replacement was sporadic and not continuous, unlike its relatives. At least four other heterodontosaurid genera are known from the same geological formations as Heterodontosaurus.
known from the same geological formations as Heterodontosaurus. The holotype specimen of Heterodontosaurus tucki (SAM-PK-K337) was discovered during the...
2005 as the stem clade consisting of Heterodontosaurus tucki and all species more closely related to Heterodontosaurus than to Parasaurolophus walkeri, Pachycephalosaurus...
SAM-PK-K1326 and SAM-PK-K1334, the Heterodontosaurus juvenile skull SAM-PK-K10487, and the complete Heterodontosaurus skull and postcrania SAM-PK-K1332...
sauropodomorph Massospondylus, as well as other heterodontosaurids like Heterodontosaurus and Lycorhinus. Remains of terrestrial crocodylomorphs, cynodonts...
and Lycorhinus tucki by Richard Anthony Thulborn in 1970 renaming Heterodontosaurus tucki, but these have failed to find recognition. Lycorhinus consors...
not known how old they were upon death. Fruitadens was similar to Heterodontosaurus in anatomy, with relatively short arms and long distal sections of...
Megapnosaurus, Dracovenator, Melanorosaurus, Massospondylus, Euskelosaurus, Heterodontosaurus, Abrictosaurus, and Lesothosaurus. In the Middle Jurassic, the sauropods...
length based on the proportions of the related South African species Heterodontosaurus tucki. However, Tianyulong had unusual proportions compared to other...
morphology when compared to the only other contemporary ornithischian Heterodontosaurus. Due to its fragmentary nature, Fabrosaurus is now seen as a nomen...
aspects are based on the almost-complete genus Heterodontosaurus. Wear facets on the crowns of Heterodontosaurus indicate occlusion across the top of the tooth...
etc.) and traditional ornithischians (Eocursor, Scutellosaurus, Heterodontosaurus, etc.). This phylogenetic position may explain why some authors consider...
diagnose the group, was found to be present in unrelated taxa like Heterodontosaurus, Protoceratops and Silvisaurus. Galton made Hypsilophodontidae paraphyletic...
clade of all archosaurs closer to Silesaurus opolensis than to either Heterodontosaurus tucki or Marasuchus lilloensis. At around the same time, Sterling...
keratinous beak. The premaxillary teeth and the first lower tooth in Heterodontosaurus are enlarged into sizeable canines. In later ornithopods, the skulls...
Jurassic ornithischian dinosaurs, including Abrictosaurus, Fabrosaurus, Heterodontosaurus, and Lesothosaurus, among others. The Forest Sandstone Formation was...
et al. (July 2021). Long JA, Perry GH, Spencer M (eds.). "A new Heterodontosaurus specimen elucidates the unique ventilatory macroevolution of ornithischian...
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