[D] Lesothosaurus diagnosticus [Su] [sG] [T]
Jurassic Early Hettangian ?Sinemurian
Upper Elliot Formation, Mafeteng District, Lesotho, South Africa
Genus - Typespecies - Skull
At least 4 skulls and associated skeletal.
Knoll (2002) described in detail a subadult, articulated, uncrushed and almost complete (incl. the lower jaw) skull (MNHN LES17) collected during a 1963 expedition in the Upper Elliot Formation at Masitise between Alwynskop and Mayeni, Lesotho. This skull missingt the rostral end of the snout (inclusive of predenatary and premaxillae) and incomplete orbits is refered by Sereno (1991) to the typespecies. Another partial skull (MNHN LES 18) from the same formation was also described by Knoll
Lesothosaurus had a small head, perhaps with small, fleshy cheeks, ridged cheek teeth, and a horny lower beak. Long, toe and shin bones show that Lesothosaurus was capable of running extremely fast. In many ways, the creature resembled a modern gazelle - a defenceless planteater on the alert at all times for danger because the only means of escaping an attacker is instant flight at high speed.
The toe and shin bones are particularly like those of a gazelle. It is possible that the fossil bones named Lesothosaurus in 1978 are actually the same as those of Fabrosaurus (\\\\\\\"Fabre\\\\\\\'s lizard\\\\\\\"), named in 1964 from a worn piece of lower jaw. The skull had big cavities for the eye and jaw muscles, an opening in front of the eye, a short, pointed snout, and a lower jaw that may have ended in a horny beak.
Teeth slightly set in from the outside of the skull and mandible suggest there were small cheeks. Lesothosaurus was a small, primitive, lightly built plant-eater with some - but not all- of the features found in ornithopods rather than other ornithischians. The long tail is typically ornithopod.