Meyasaurus faurai (Vidal 1915, M. dizromerali Evans and Barbadillo 1996) Early Cretaceous, ~10 cm skull length was considered an early lizard and a sphenodontid, but with the first rib atypically (for lizards) associated with the fifth vertebra. Here Meyasaurus was derived from a sister to Lacertulus at the base of the squamates. Meyasaurus phylogenetically preceded Huehuecuetzpalli in the Tritosauria.
Distinct from Lacertulus, the skull of Meyasaurus had a more sharply angled rostrum and a longer temporal (postorbital) area. The postorbital did not descend as far. The premaxilla dorsal process extended beyond the naris. The parietal was larger. The pineal opening was smaller and further forward. The frontal-parietal suture was straight and wider than the frontal-nasal suture. The frontal was narrower between the orbits. The teeth were tiny and the posterior teeth had twin cusps (bicuspid).
The cervicals of Meyasaurus were more robust with large paddle-shaped ribs.
The scapulocoracoid was fenestrated anteriorly, as in all other lizards, and the clavicle was more robust. The humerus was expanded distally. Metacarpal 4 was shorter than 3.
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