Acta Zoologica Cracoviensia, 31() 1988
A cladogram of the pleurodiran turtles
Abstract:
A cladogram for eleven pleurodiran genera plus the family Chelidae is tested using shared derived characters of the skull and postcranium. The Triassic pleurodire Proterochersis is the sister group of all other pleurodires based on the presence in all other pleurodires of the following characters: absence of cleithra, three or less supramarginals, mesoplastra not meeting in midline. The Jurassic pleurodire Platychelys is the sister group of Pelomedusidae plus Chelidae based on equidimensional or absent mesoplastra and no supramarginal scutes. The monophyletic groups of pelomedusids are hypothesized: Bothremys, Taphrosphys, Pelomedusa, and Pelusios characterized by the occipital condyle formed only by the exoccipitals; and Podocnemis, Peltocephalus, Erymnochelys, Shweboemys, and Stereogenys characterized by the hypertrophied carotid canal.
