PIMUZ-A-III-0192

PIMUZ A/III 0192 (Rossman 2002) Here the Rossman “Brazilosaurus” nests near the base of the Mesosauria, whether using the Rossman data as is, or pulling slightly different traits out. Due to severe crushing elements from the other side of the skull made it appear that the skull lacked fenestration following the generally accepted but mistaken hypothesis that all mesosaurs lacked temporal fenestra. Note the tiny forelimbs and deep tail chevrons. Low dorsal spines and gracile ribs are also noteworthy.

Psilotrachelosaurus toeplitschi (Nopcsa 1928, Rieppel 1993; Middle Triassic) was originally considered the sister taxon of the Serpianosaurus-Neusticosaurus (Pachypleurosaurus) clade with a relatively short humerus, ossified distal carpal and tarsal 4 and a relatively broad pubis. In the large reptile tree this taxon nests basal to all mesosaurs and the sister to thalattosaurs + Wumengosaurus + ichthyosaurs.

Nopcsa F 1928. Palaeontological notes on reptiles. Geologica Hungaria. Ser. Palaeontologica 1:3-84.

Rieppel O 1993. Status fo the pachypleurosoid Psilotrachelosaurus toeplitschi Nopcsa (Reptilia, Sauropterygia) from the Middle Triassic of Austria. Fieldinana (Geology) 27:1-17.

Rossmann T 2002. Studien an Mesosauriern (Amniota inc. sed., Mesosauridae): 3. Neue Aspekte zur Anatmie, Erhaltung und Paläoökologie aufgrund der Exemplare im Paläontologischen Institut der Universität Zurich. Neues Jahrbuch fur Geologie und Paläontologie, Abhandlungen 224, 197-221.

Shikama T 1966. On a reptilian skeleton from the Palaeozoic formation of San Paulo, Brazil. Transactions and Proceedings of the Palaeontological Society of Japan, New Series 64:351-358.

Marine Younginiformes

Galesphyrus

Claudiosaurus

Enaliosauria

Anarosaurus

Parapachypleurosauria

Luopingosaurus

Mesosauria

PIMUZ-A-III-0192

SMF R 4710

Stereosternum

Mesosaurus