Milleretta rubidgei (Broom 1938) specimen RC70 Late Permian, ~3.5 cm skull length was derived from a sister to Milleretta RC14 and phylogenetically preceded Odontochelys, Stephanospondylus (which makes it a turtle ancestor) and Saurorictus (ancestral to all later lepidosauromorphs.
Distinct from the RC14 specimen of Milleretta, the skull of RC70 had a lower, sharper rostral profile. The indentation at the rear of the skull was deeper, shifting the quadratojugal forward. There was no indication of any lateral temporal opening. The supraoccipital was wider. The parsphenoid lateral processes were less prominent. The teeth are longer, yet this was likely still a plant-eater. The parietal was relatively shorter and wider. The postparietal bones (supratempora and tabular) are wider apart and directed more laterally.
My guess, based on phylogenetic bracketing, is that this specimen also has wide rib that are also individually wide, like the RC14 specimen and Odontodchelyls. |