Phylum Chordata Rank Family | Higher classification Nothosaur Order Nothosaur | |
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Suborder †PachypleurosauriaNopcsa, 1928 Similar Nothosaur, Sauropterygia, Pistosauroidea, Neusticosaurus, Placodont | ||
Dinosaur park 3 rhomaleosaurus and pachypleurosaurus
Pachypleurosaurs were primitive sauropterygian reptiles that vaguely resembled aquatic lizards, and were limited to the Triassic period. They were elongate animals, ranging in size from 20 cm to about a metre in length, with small heads, long necks, paddle-like limbs, and long deep tails. The limb girdles are greatly reduced, so it is unlikely these animals could move about on land. The widely spaced peg-like teeth project at the front of the jaws, indicate that these animals fed on fish.
Pachypleurosaurs were originally and are often still included within the Nothosauroidea (Carroll 1988, Benton 2004). In some cladistic classifications however (Rieppel 2000), they are considered the sister group to the Eusauropterygia, the clade that includes the nothosaurs and plesiosaurs.