Nothosauria

Nothosauria is an extinct suborder of marine reptiles that lived during the Triassic period. These creatures were semi-aquatic, meaning they could inhabit both land and water, though they were primarily adapted for life in the sea. Nothosaurs were part of the larger group known as Sauropterygia, which also includes the later plesiosaurs.

Fossil evidence suggests that nothosaurs varied in size, with some reaching lengths of up to 4 meters (about 13 feet). They possessed elongated bodies, long necks, and four paddle-like limbs that would have been effective for swimming. Their skulls were often broad, and their jaws were filled with sharp, conical teeth, indicating a diet of fish and other small marine animals. Some species had nostrils positioned high on their skulls, which would have been advantageous for breathing while mostly submerged.

The distribution of nothosaur fossils indicates they were widespread across the Tethys Sea and other marine environments during the Triassic. Their ability to return to land suggests they likely nested on shorelines, similar to modern sea turtles. Nothosaurs represent an early evolutionary step in the development of marine reptiles, showcasing adaptations for a fully aquatic or semi-aquatic lifestyle. Their lineage eventually gave rise to more specialized marine reptiles, though nothosaurs themselves went extinct by the end of the Triassic period, likely due to environmental changes and competition.