Triassic Keichousaurus hui Swimming Reptile Fossil

Description: This is a good quality ventral (underside) specimen of this intriguing genus. Its death pose is somewhat awkward, head and neck bent, facing left. Note the excellent bone detail of the back legs, tail and ribs.

Imagine being able to afford a swimming reptile from the Triassic. Until about four years ago these were available in large numbers on the world market. The Chinese authorities since then have prohibited the export of almost all fossils. Accordingly, this is a good time to acquire one of these specimens before they become scarce and much more expensive.

Keichousaurus is a genus of marine reptile in the pachypleurosaur family which went extinct at the close of the Triassic in the Triassic-Jurassic extinction event. The name derives from Kweichow (now Guizhou Province) in China where the first fossil specimen was discovered in 1957. They are among the most common sauropterygian fossils recovered and are often found as nearly complete, articulated skeletons, making them popular among collectors. Keichousaurus, and the pachypleurosaur family broadly, are sometimes classified within Nothosauroidea, but are otherwise listed as a separate, more primitive lineage within Sauropterygia.

Keichousaurus, like all sauropterygians, was highly adapted to the aquatic environment. Individuals of this genus ranged from 15 - 30 cm in length, and had both long necks and long tails, with elongated, five-toed feet. The pointed head and sharp teeth in this genus also indicate that they were fish-eaters. Some recovered specimens feature an especially developed ulna suggesting they may have spent some time on land or in marshes. In addition fossil evidence suggest also a pair of fossilized pregnant marine reptiles called Keichousaurus hui, show they had a mobile pelvis to give birth to live young rather than laying eggs.