Teleosauridae

Teleosauridae is a family of extinct typically marine crocodylomorphs similar to the modern gharial that lived during the Jurassic period. Teleosaurids were thalattosuchians closely related to the fully aquatic metriorhynchoids, but were less adapted to an open-ocean, pelagic lifestyle. The family was originally coined to include all the semi-aquatic (i.e. non-metriorhynchoid) thalattosuchians and was equivalent to the modern superfamily Teleosauroidea. However, as teleosauroid relationships and diversity was better studied in the 21st century, the division of teleosauroids into two distinct evolutionary lineages led to the establishment of Teleosauridae as a more restrictive family within the group, together with its sister family Machimosauridae.

Amongst teleosauroids, teleosaurids were generally smaller and less common than machimosaurids, suggesting the two families occupied different niches, similar to modern species of crocodilians. However, teleosaurids were more diverse than machimosaurids, with generalist coastal predators (Mystriosaurus), long-snouted marine piscivores (Bathysuchus), and potentially even long-snouted, semi-terrestrial predators (Teleosaurus). Additionally, teleosaurids occupied a wider range of habitats than machimosaurids, from semi-marine coasts and estuaries, the open-ocean, freshwater, and potentially even semi-terrestrial environments.