Cryptoclididae is a family of medium-sized plesiosaurs that existed from the Middle Jurassic to the Early Cretaceous. They had long necks, broad and short skulls and densely packed teeth. They fed on small soft-bodied preys such as small fish and crustaceans. The earliest members of the family appeared during the early Bajocian, and they represented the dominant group of long-necked plesiosaurs during the latter half of the Jurassic.[1]
In 2010, two supposed late Cretaceous members of the group were reclassified as other kinds of plesiosauroids. Kaiwhekea was reclassified to Leptocleididae, and Aristonectes was transferred to Elasmosauridae.[2]
Cladogram based on Ketchum and Benson (2010):[2]