Saurosternonis anextinctgenusofneodiapsidreptilefrom theLate PermianofSouth Africa.It is based on a partial skeleton split between two slabs ofsandstonefrom theDaptocephalusAssemblage Zone.[1]Saurosternonwas one of the earliest smalllizard-like reptiles to be discovered in Permian deposits of theKaroo Supergroup,preceding later discoveries such asPaliguana,Youngina,Palaeagama,andLacertulus.The skeleton is mostly complete, though missing the head. Most of the original bone had decayed away by the time the fossil was discovered, leaving perfect molds in the sandstone slabs. What little bone remained was removed with acid by museum preparators, and the specimen was cast with latex to reconstruct the original bone shape.[2]
The affinities ofSaurosternonare uncertain. Several studies interpreted it as one of the earliestlepidosauromorphs,the reptile group includingsquamates(lizards and snakes),rhynchocephalians(tuataraand kin), and their close relatives.[3]One study proposed thatSaurosternonwas a "paliguanid", a suggested (and likely invalid) ancestral family of lizards also includingPaliguanaandPalaeagama.[2]More recently it has generally been considered an early neodiapsid outside ofSauria(thecrown groupof reptiles).[4][5]
