Nanchangosaurus

Nanchangosaurus was a large aquatic reptile native to the middle Triassic of China. It was named after the area in China, Nanchang, where it was found. It was about three feet (one meter) in length, and probably fed on fish or used its long jaws to probe for aquatic invertebrates. It resembled the ichthyosaurs in build, and may be related to them.

Anatomy
Nanchangosaurus resembled a cross between an ichthyosaur and a crocodilian. It had a fusiform body, similar to a dolphin or an ichthyosaur, paddle-like limbs; with forelimbs being larger than hindlimbs, and a crocodilian-like tail for swimming through the water. It had bony scutes on its back, like an alligator, but had a long snout filled with teeth, like an ichthyosaur or a river dolphin.

Classification
Nanchangosaurus is a member of the Hupehsuchia, a group that includes the very similar Hupehsuchus. In fact, the two may be congeneric. There are a few differences between the two species. Hupehsuchus had heavier armor and more divided ridge spines than the two. Other than Hupehsuchus, there is little else known about Nanchangosaurus relatives. They have sometimes been referred to as ancestors of the ichthyosaurs, because of their streamlined shape, long jaws, and paddle-like hands, as well as the discovery of polydactyly in the fins of Hupehsuchus; just like the ichthyosaurs. However, a gap in the skulls suggests that they may be related to archosaurs instead. Some people even put them in the Eosuchia, a group of early diapsid reptiles.