Heterodontosauridae

Heterodontosaurids Temporal range: Early Jurassic – Early Cretaceous, 200–140 Ma PreꞒ Ꞓ O S D C P T J K Pg N Possible Late Triassic record
Cast of specimen SAM-PK-K1332 of Heterodontosaurus tucki, University of California Museum of Palaeontology
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	†Ornithischia
Clade:	†Saphornithischia
Family:	†Heterodontosauridae Romer, 1966 (Kuhn, 1966)
Subgroups[1]
†Echinodon †Fruitadens †Geranosaurus †Tianyulong †Heterodontosaurinae Sereno, 2012[1] †Abrictosaurus †Heterodontosaurus †Lycorhinus †Manidens †Pegomastax

Heterodontosauridae is a family of ornithischian dinosaurs that were likely among the most basal (primitive) members of the group. Their phylogenetic placement is uncertain but they are most commonly found to be primitive, outside of the group Genasauria.^[2] Although their fossils are relatively rare and their group small in numbers, they have been found on all continents except Australia and Antarctica, with a range spanning the Early Jurassic to the Early Cretaceous.

Heterodontosaurids were fox-sized dinosaurs less than 2 metres (6.6 feet) in length, including a long tail. They are known mainly for their characteristic teeth, including enlarged canine-like tusks and cheek teeth adapted for chewing, analogous to those of Cretaceous hadrosaurids. Their diet was herbivorous or possibly omnivorous.