Thalattosauria

Thalattosauria is an extinct group of reptiles that lived during the Triassic Period. Its members were mostly marine, and some had long snouts adapted to aquatic life.

Diapsid: A reptile with two openings on each side of the skull behind the eye. Thalattosaurs belong among diapsid reptiles, a broad group defined by this skull architecture.
Thalattosaurus: A genus of Triassic marine reptiles with a long, narrow snout and numerous teeth. This genus gives Thalattosauria its name and exemplifies its long-snouted forms.
Triassic: The geological period from about 252 to 201 million years ago, between the Permian and Jurassic. Thalattosaurs lived during this period, when marine ecosystems diversified after the end-Permian extinction.
Phylogenetic nomenclature: A system of naming biological groups according to evolutionary relationships. Different analyses place thalattosaur families and related reptiles in varying positions on the reptile family tree.
Sauropterygia: An extinct group of aquatic reptiles that included plesiosaurs and placodonts. Sauropterygians were other marine reptiles of the Mesozoic, but were not thalattosaurs.
Nectosaurus: A genus of Triassic marine reptile known from fossils found in California. Its elongate jaws illustrate the aquatic feeding specializations found in some thalattosaurs.
Middle Triassic: The middle epoch of the Triassic Period, spanning roughly 247 to 237 million years ago. Many thalattosaur fossils come from this interval, documenting the group's early diversification.
Fossil: Preserved remains or traces of organisms from past geological ages. Most knowledge of thalattosaur diversity depends on fragmentary and unevenly preserved fossils.
Ichthyosaur: An extinct marine reptile group with streamlined bodies and limbs transformed into flippers. Ichthyosaurs shared Triassic seas with thalattosaurs but evolved a more fishlike body plan.
Askeptosaurus: A genus of long-snouted thalattosaur from Middle Triassic marine deposits in Europe. Its well-known skull offers a clear example of the group's long-jawed anatomy.

Linked from 1 page

PlacodontiaCompared with: Thalattosaurs provide another Triassic marine-reptile comparison, with feeding adaptations unlike placodont crushing teeth.