Abrictosaurus

Abrictosaurus is known from only two fossils: a partial skull and skeleton, plus a fragmentary skull.1

Unlike some relatives, its cheek teeth were widely spaced with low crowns, more like early ornithischians.1

One fossil had impressive tusks: an upper one 10.5 mm tall and a lower one 17 mm tall, serrated only on the front edge.1

It lived in a hot, half-dry environment with sand dunes and seasonal floods, alongside dinosaurs like Massospondylus and Heterodontosaurus.1

The first scientist who described it thought the tusks were just in males, so he called the female fossil 'consors', meaning partner or spouse.12

Abrictosaurus had small, weak forelimbs with only four finger bones in the fourth and fifth fingers, fewer than its relative Heterodontosaurus.1