cryptocleidids

Cryptocleidids are a superfamily of plesiosaurs, a group of marine reptiles that lived during the Mesozoic Era. They are characterized by their long necks and paddle-like limbs, adaptations for an aquatic lifestyle. Cryptocleidids are distinguished from other plesiosaurs by specific anatomical features, primarily in their skull and pectoral girdle. They are known from fossils found in various parts of the world, indicating a wide geographic distribution.

These marine reptiles are believed to have been predators, likely feeding on fish and other marine organisms. The exact phylogenetic relationships of cryptocleidids within the broader plesiosaur group have been a subject of study, with ongoing research refining our understanding of their evolutionary history. The superfamily includes several well-known genera and species, some of which are among the most complete plesiosaur specimens ever discovered. Their fossils provide valuable insights into the biodiversity and ecosystems of ancient oceans.