Temporal Range: Middle to Late Triassic (241-223 Mya)
Length: 2 metres
– Discovery: Thalattosaurus was first named in 1904 by American paleontologist John C. Merriam, alongside the creation of thalattosauria order. The original fossil specimen was recovered from Wapiti Lake in British Columbia, Canada. This fossil contained parts of the animals skull, an incomplete jaw and some ribs. Since then, a number specimens have been recovered from Triassic deposits in both the USA and Canada.
– Description: Similarly to its relatives, Thalattosaurus was an excellent swimmer. It was a very lengthy animal, measuring up to 2 metres long with a body that was effectively streamlined. It had a very long, flattened tail which have been used as the primary method of locomotion through the water. The limbs of Thalattosaurus were fairly short but its feet were webbed and paddle-like, which would have helped the animal turn sharply in the water when hunting prey.
It is believed that Thalattosaurus would have hunted in shallow waters near the shoreline, a theory highlighted by the fact that the fossil specimens recovered from Wapiti Lake were found in sandstone. In addition, the flattened tail and clawed feet would have provided assistance against the force of surf when clambering up the shore. Although all thalattosaurs were believed to spend time both on land and in the water, it is unlikely that Thalattosaurus would have ventured into deep waters. The skull itself was fairly flat but housed a number of sharp teeth that would have effectively crushed any shelled prey items as well as been used to snatch up agile fish.
(Restoration Source: http://datab.us/i/thalattosaur)