Helveticosaurus is known from a nearly complete holotype which includes the premaxilla, maxilla, prefrontal, postfrontal, postorbital, squamosal, dentary and a poscranial skeleton. Several disarticulated elements are also known including teeth, portions of the snout and poscranial elements.[1] Helveticosaurus is about 2 meters long from snout to tail.[2] It possessed many features that were adaptations to a marine lifestyle in the shallow-sea environment that existed in Europe at the time when much of the continent was part of the Tethys Ocean. The long, flexible tail is similar to what can be seen in other extinct marine reptiles such as thalattosaurs, and it probably propelled itself through the water by means of lateral undulation. However, Helveticosaurus also possessed a robust pector