Pronunciation: lee-soo-too-SOR-us
Meaning: Lizard from Lesotho
Author/s: Galton (1978)
Synonyms: None known
First Discovery: Mafeteng, Lesotho
Discovery Chart Position: #261
Lesothosaurus diagnosticus
With a name like Lesothosaurus, this herbivorous ornithischian dinosaur could only be from one place: Lesotho (lee-soo-too), the world's southern-most landlocked country, being completely surrounded by South Africa, and one of the few places still classed as a Kingdom.
Based on material previously assigned to Fabrosaurus australis by Richard Thulborn in the early seventies, the "Lizard from Lesotho" was small, sleek and streamlined. Its legs were much longer than its arms and ideally suited to tearing around the hot arid Lesotho plains, while its hands were short with four stiff fingers (five if you count the fifth stump), which were ill-equipped for grasping. Likewise, its mouth was ill-equipped for chewing 'cos it didn't have cheeks, so fodder was roughly snipped by the keratinous beak which tipped its upper and lower jaw, then swallowed as is to be processed in the stomach by gastroliths.
Classification-wise, Lesothosaurus has been all around the ornithischian family tree and tagged as an ornithopod, the most primitive of all known ornithischians, a basal neornithischian, a juvenile Stormbergia and a misunderstood species of Fabrosaurus by various experts at various times. In 2008, the results of Butler, Upchurch and Norman's analysis pointed to a primitive form of thyreophoran — one of the armoured ornithischians or "shield bearers" — which, funnily enough, would make it the only known shield bearer that doesn't bear a shield.
Based on material previously assigned to Fabrosaurus australis by Richard Thulborn in the early seventies, the "Lizard from Lesotho" was small, sleek and streamlined. Its legs were much longer than its arms and ideally suited to tearing around the hot arid Lesotho plains, while its hands were short with four stiff fingers (five if you count the fifth stump), which were ill-equipped for grasping. Likewise, its mouth was ill-equipped for chewing 'cos it didn't have cheeks, so fodder was roughly snipped by the keratinous beak which tipped its upper and lower jaw, then swallowed as is to be processed in the stomach by gastroliths.
Classification-wise, Lesothosaurus has been all around the ornithischian family tree and tagged as an ornithopod, the most primitive of all known ornithischians, a basal neornithischian, a juvenile Stormbergia and a misunderstood species of Fabrosaurus by various experts at various times. In 2008, the results of Butler, Upchurch and Norman's analysis pointed to a primitive form of thyreophoran — one of the armoured ornithischians or "shield bearers" — which, funnily enough, would make it the only known shield bearer that doesn't bear a shield.
(Diagnostic Lesotho Lizard)Etymology
Lesothosaurus is derived from "Lesotho" (its place of discovery) and the Greek "sauros" (lizard). The species epithet, diagnosticus, refers to the "fact that this species provided the original recognition and diagnosis of the family Fabrosauridae" (Galton, 1972).
Discovery
The first remains of Lesothosaurus were discovered on Likhoele Mountain in the Upper Elliot Formation (Stormberg Group), Masitise, Mafeteng District, Lesotho (previously called Basutoland), by Mr K.A. Kermack and Mrs F. Mussett during an expedition from University College, London, in 1963-1964. The syntypes consist of BMNH RUB17—the disjointed remains of two individuals, one bigger than the other, including most of one articulated, uncrushed and almost complete skull, and BMNH RUB23—a partial skull.
Referred material, discovered in 1967-1968 in Lesotho by a joint expedition from the British Museum of Natural History, London University College, Yale University and the South African Museum, includes BMNH R11956 (a partial skull), BMNH R11002/R11003/R11004 (two hip bones, and a partial skull and neck), BMNH R8501 (a nearly complete skull), SAM-PK-K400/401 (a hip bone and partial skull from Likhoele), and SAM-PK-1106 (a partial skeleton from Dangershoek).
