Here (Fig. 1) just a little color and phylogenetic bracketing adds in the missing pieces from the Pintosaurus skull. The upper portions had weathered away, but are here restored.
Distinct from sister taxa,
Pintosaurus had only three teeth in the premaxilla, and it appeared to have a posterolateral process of the premaxilla. The large palatal fangs on the palatine are also unique to this genus. But when Contritosaurus (aka Phaanthosaurus, Fig. 2) is added it shares the trait of three large premaxillary teeth, but the naris is anterior on a transverse premaxilla. This clade has an unusual narial fossa (depression).
Like their sister, Coletta (Fig. 3, Gow 2000, Modesto, Damiani and Sues 2002, Early Triassic, GHG 228), these genera likely had upper temporal fenestra. They nest as derived owenettids and stem lepidosauriformes.
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