Dinocephalosaurus is a genus of long necked, aquatic protorosaur that inhabited the Triassic seas of China. The genus contains the type and only known species, D. orientalis, which was named by Chun Li in 2003. Unlike other long-necked protorosaurs, Dinocephalosaurus convergently evolved a long neck not through elongation of individual neck vertebrae, but through the addition of neck vertebrae that each had a moderate length. As indicated by phylogenetic analyses, it belonged in a separate lineage that also included at least its closest relative Pectodens, which was named the Dinocephalosauridae in 2021. Like tanystropheids, however, Dinocephalosaurus probably used its long neck to hunt, utilizing the fang-like teeth of its jaws to ensnare prey; proposals that it employed suction feeding have not been universally accepted. It was probably a marine animal by necessity, as suggested by the poorly-ossified and paddle-like limbs which would have prevented it from going ashore.
Sauropterygia is an extinct taxon of diverse, aquatic reptiles that developed from terrestrial ancestors soon after the end-Permian extinction and flourished during the Triassic before all except for the Plesiosauria became extinct at the end of that period. The plesiosaurs would continue to diversify until the end of the Mesozoic. Sauropterygians are united by a radical adaptation of their pectoral girdle, adapted to support powerful flipper strokes. Some later sauropterygians, such as the pliosaurs, developed a similar mechanism in their pelvis.
Nothosaurs were Triassic marine sauropterygian reptiles. They averaged about 3 metres (10 ft) in length, with a long body and tail. The feet were paddle-like, and are known to have been webbed in life, to help power the animal when swimming. The neck was quite long, and the head was elongated and flattened, and relatively small in relation to the body. The margins of the long jaws were equipped with numerous sharp outward-pointing teeth, indicating a diet of fish and squid.
Nothosaurus is an extinct genus of sauropterygian reptile from the Triassic period, approximately 240–210 million years ago, with fossils being distributed from North Africa and Europe to China. It is the best known member of the nothosaur order.
Placodonts are an extinct order of marine reptiles that lived during the Triassic period, becoming extinct at the end of the period. They were part of Sauropterygia, the group that includes plesiosaurs. Placodonts were generally between 1 and 2 m in length, with some of the largest measuring 3 m (9.8 ft) long.
Euryapsida is a polyphyletic group of sauropsids that are distinguished by a single temporal fenestra, an opening behind the orbit, under which the post-orbital and squamosal bones articulate. They are different from Synapsida, which also have a single opening behind the orbit, by the placement of the fenestra. In synapsids, this opening is below the articulation of the post-orbital and squamosal bones. It is now commonly believed that euryapsids are in fact diapsids that lost the lower temporal fenestra. Euryapsids are usually considered entirely extinct, although turtles might be part of the sauropterygian clade while other authors disagree. Euryapsida may also be a synonym of Sauropterygia sensu lato.
Pachypleurosauria is an extinct clade of primitive sauropterygian reptiles from the Triassic period. Pachypleurosaurs vaguely resembled aquatic lizards, with elongate forms ranging in size from 0.2–1 metre (0.66–3.28 ft), with small heads, long necks, paddle-like limbs, and long, deep tails. The limb girdles are greatly reduced, so it is unlikely these animals could move about on land. The widely spaced peg-like teeth project at the front of the jaws, indicating that these animals fed on fish. In the species Prosantosaurus, it was observed that they fed on small fishes and crustaceans which they devoured entirely and that its teeth regrew after they broke off. This was the first observation of tooth replacement in a European pachypleurosaur, with the only other discovery of such an event having been made in China.
Thalattosauria is an extinct order of prehistoric marine reptiles that lived in the Middle to Late Triassic. Thalattosaurs were diverse in size and shape, and are divided into two superfamilies: Askeptosauroidea and Thalattosauroidea. Askeptosauroids were endemic to the Tethys Ocean, their fossils have been found in Europe and China, and they were likely semiaquatic fish eaters with straight snouts and decent terrestrial abilities. Thalattosauroids were more specialized for aquatic life and most had unusual downturned snouts and crushing dentition. Thalattosauroids lived along the coasts of both Panthalassa and the Tethys Ocean, and were most diverse in China and western North America. The largest species of thalattosaurs grew to over 4 meters (13 feet) in length, including a long, flattened tail utilized in underwater propulsion. Although thalattosaurs bore a superficial resemblance to lizards, their exact relationships are unresolved. They are widely accepted as diapsids, but experts have variously placed them on the reptile family tree among Lepidosauromorpha, Archosauromorpha, ichthyosaurs, and/or other marine reptiles.
The Guanling Formation is a Middle Triassic geologic formation in southwestern China.
Nothosauridae are an extinct family of carnivorous aquatic sauropterygian reptiles from the Triassic time period of China, France, Germany, Israel, Italy, Netherlands, Russia, Switzerland, and northern Africa.
Sinosaurosphargis is an extinct genus of basal marine saurosphargid reptile known from the Middle Triassic Guanling Formation of Yunnan and Guizhou Provinces, southwestern China. It contains a single species, Sinosaurosphargis yunguiensis.
Wumengosaurus is an extinct aquatic reptile from the Middle Triassic Guanling Formation of Guizhou, southwestern China. It was originally described as a basal eosauropterygian and usually is recovered as such by phylogenetic analyses, although one phylogeny has placed it as the sister taxon to Ichthyosauromorpha while refraining from a formal re-positioning. It was a relatively small reptile, measuring 95.5–130.5 cm (3.13–4.28 ft) in total body length.
Largocephalosaurus is an extinct genus of basal saurosphargid, a marine reptile known from the Middle Triassic Guanling Formation of Yunnan and Guizhou Provinces, southwestern China. It contains a type species, Largocephalosaurus polycarpon, and a second species L. qianensis.
Placodontiformes is an extinct clade of sauropterygian marine reptiles that includes placodonts and the non-placodont Palatodonta. It was erected in 2013 with the description of Palatodonta. Placodontiformes is the most basal clade of Sauropterygia and the sister group of Eosauropterygia, which includes all other sauropterygians.
Parahupehsuchus is an extinct genus of hupehsuchian marine reptiles from the Early Triassic of China. The genus is monotypic, known from the single species Parahupehsuchus longus and based on a single specimen. Like other hupehsuchians, it had an elongated torso, a tail nearly as long as the rest of the body, short and paddle-like limbs, extra bones in the fore- and hind limbs, thick ribs and gastralia, neural spines of the vertebrae split into two parts, and bony plates over the neural spines. It differs from other hupehsuchians in having an even more elongated body and wider ribs that touch along their edges and have no spaces between them. The ribs connect with gastralia on the underside of the torso to form a bony "tube" around the body wall.
Eohupehsuchus is a genus of extinct aquatic diapsid from the Upper Spathian of Hubei Province, located in Central China. The genus is monotypic and belongs to the order Hupehsuchia, whose members are characterized by toothless beak-like snouts, a row of dermal plates along their backs, and aquatic adaptations including paddle-shaped limbs and fusiform bodies with pachyostotic ribs.
Eretmorhipis is an extinct genus of hupehsuchian marine reptiles from the Early Triassic of China. It is currently known from two specimens that were discovered in an exposure of the Jialingjiang Formation in Yuan'an County, Hubei, and referred to the newly named species Eretmorhipis carrolldongi in 2015.
Saurosphargidae is an extinct family of marine reptiles known from the Early Triassic and early Middle Triassic of Europe and China.
The Zhuganpo Formation is a Triassic geologic unit found in southern China. It has historically been known as the Zhuganpo Member of the Falang Formation. A diverse fossil assemblage known as the Xingyi biota or Xingyi Fauna can be found in the upper part of the Zhuganpo Formation. Fossils of the Xingyi biota include articulated skeletons of marine reptiles, abundant fish, and a plentiful assortment of invertebrates indicating a Ladinian to Carnian age for the sediments of the formation.
Chusaurus is an extinct genus of pachypleurosaurid known from the Early Triassic Nanzhang-Yuan’an Fauna in the South China block. The two known specimens of Chusaurus were found in Hubei Province, China, dating back to the Olenekian age of the Early Triassic period. The genus contains a single species, Chusaurus xiangensis
