Viviparity in a Triassic marine archosauromorph reptile

Eggs or embryos have been reported in various groups of fossil reptiles, whereviviparity is a common mode of reproduction in aquatic taxa such as the ichthyopterygians, some groups of sauropterygians, mosasauroids, some taxa of choristoderans and certain protorosaurs.Here, we describe a complete embryo of a marine protorosaur, based on a well-preserved, curledup skeleton. The new discovery is referred to a taxon closely related to the remarkable longnecked Dinocephalosaurus. It further confirmed viviparity in an archosauromorph group and indicates an increasing taxonomic diversity not only within this group, but of Triassic marine reptiles in general.