Plesiosaurus

The Plesiosaurus was a large marine reptile that lived during the early part of the Jurassic period.

It was distinguished by its small head, long and slender neck, broad turtle-like body, short tail, and two pairs of large, elongated paddles. The plesiosaurus shown in Vorg's miniscope was brownish green and was mildly aggressive. It was intelligent enough to be controlled by the miniscope. (DW: Carnival of Monsters)

In an alternate universe, the Plesiosaurus was one of the creatures bought back from extinction by the Silurians. (NA: Blood Heat)