Purranisaurus is an extinct genus of marine crocodyliform from the Late Jurassic aged Vaca Muerta of Argentina. Rusconi originally regarded Purranisaurus potens (the type species) to be a plesiosaur; however, Gasparini demonstrated that it was in fact a metriorhynchid crocodyliform, and that may be a junior synonym of Metriorhynchus. It was about 3.3 m (11 ft) long.

Taxonomy and phylogeny

Restoration of 'Metriorhynchus' casamiquelai, which was at one point assigned to Purranisaurus

In the 2000s phylogenetic analysis has shown that Purranisaurus is a distinct metriorhynchid genus. A subsequent study expanded the genus Purranisaurus to include Metriorhynchus casamiquelai and M. westermanni. Following the re-description of the holotype of the type species, only that species is now referred to Purranisaurus.