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 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.
Tanystropheus is an extinct genus of archosauromorph reptile which lived during the Triassic Period in Europe, Asia, and North America. It is recognisable by its extremely elongated neck, longer than the torso and tail combined. The neck was composed of 13 vertebrae strengthened by extensive cervical ribs. Tanystropheus is one of the most well-described non-archosauriform archosauromorphs, known from numerous fossils, including nearly complete skeletons. Some species within the genus may have reached a total length of 6 meters (20 ft), making Tanystropheus the longest non-archosauriform archosauromorph as well. Tanystropheus is the namesake of the family Tanystropheidae, a clade collecting many long-necked Triassic archosauromorphs previously described as "protorosaurs" or "prolacertiforms".
Macrocnemus is an extinct genus of archosauromorph reptile known from the Middle Triassic of Europe and China. Macrocnemus is a member of the Tanystropheidae family and includes three species. Macrocnemus bassanii, the first species to be named and described, is known from the Besano Formation and adjacent paleontological sites in the Italian and Swiss Alps. Macrocnemus fuyuanensis, on the other hand, is known from the Zhuganpo Formation in southern China. A third species, Macrocnemus obristi, is known from the Prosanto Formation of Switzerland and is characterized by gracile limbs. The name Macrocnemus is Greek for "long tibia".
The Guanling Formation is a Middle Triassic geologic formation in southwestern China.
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.
Diandongosaurus is an extinct genus of eosauropterygian known from the lower Middle Triassic of Yunnan Province, southwestern China. It is known from the holotype IVPP V 17761, a complete and articulated skeleton with skull, which was found in the middle Triassic Lagerstätte of the Guanling Formation. It was first named by Qing-Hua Shang, Xiao-Chun Wu, Cun Li in 2011 and the type species is Diandongosaurus acutidentatus. A referred specimen suggests a total body length of 34 cm (13 in).
Luoxiongichthys is an extinct genus of basal actinopterygian known from the lower Middle Triassic of Luoxiong Town, Luoping County of Yunnan Province, southwestern China.
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.
Diandongosuchus is an extinct genus of archosauriform reptile, possibly a member of the Phytosauria, known from the Middle Triassic of China. The type species Diandongosuchus fuyuanensis was named in 2012 from the Zhuganpo Formation of Yunnan Province. It is a marine species that shows similarities with another Chinese Triassic species called Qianosuchus mixtus, although it has fewer adaptations toward marine life. It was originally classified as the basal-most member of the pseudosuchian clade Poposauroidea. However, a subsequent study conducted by Stocker et al. indicated it to be the basalmost known phytosaur instead.
Tanystropheidae is an extinct family of mostly marine archosauromorph reptiles that lived throughout the Triassic Period. They are characterized by their long, stiff necks formed from elongated cervical vertebrae with very long cervical ribs. Some tanystropheids such as Tanystropheus had necks that were several meters long, longer than the rest of their bodies.
Atopodentatus is an extinct genus of basal sauropterygian known from the early Middle Triassic (Anisian) of Guanling Formation in Luoping County, Yunnan Province, southwestern China. It contains a single species, Atopodentatus unicus. It is thought to have lived between 247 and 240 million years ago, during the Middle Triassic period, about six million years after the Permian extinction. Atopodentatus was an herbivorous marine reptile, although marine reptiles are usually omnivores or carnivores.
Kwangsisaurus is an extinct genus of a basal pistosauroid known from the Early or Middle Triassic of Guangxi, southern China. It contains a single species, Kwangsisaurus orientalis.
Saurosphargidae is an extinct family of marine reptiles known from the Early Triassic and early Middle Triassic of Europe and China.
Shringasaurus is an extinct genus of archosauromorph reptile from the Middle Triassic (Anisian) of India. It is known from the type and only known species, S. indicus. Shringasaurus is known from the Denwa Formation in the state of Madhya Pradesh. Shringasaurus was an allokotosaur, a group of unusual herbivorous reptiles from the Triassic, and is most closely related to the smaller and better known Azendohsaurus in the family Azendohsauridae. Like some ceratopsid dinosaurs, Shringasaurus had two large horns over its eyes that faced up and forwards from its skull. Shringasaurus also bears convergent physical similarities to sauropodomorph dinosaurs, such as its long neck, its shoulders and forelimbs, and the shape of its teeth. Shringasaurus possibly occupied a similar ecological niche as a large browsing herbivore before such dinosaurs had evolved.
Pectodens is an extinct genus of archosauromorph reptile which lived during the Middle Triassic in China. The type and only species of the genus is P. zhenyuensis, named by Chun Li and colleagues in 2017. It was a member of the Archosauromorpha, specifically part of the unnatural grouping Protorosauria. However, an unusual combination of traits similar and dissimilar to other protorosaurs initially led to confusion over its evolutionary relationships. In 2021, it was placed in a newly-established group, Dinocephalosauridae, along with its closest relative Dinocephalosaurus.
Rhombopholis is an extinct genus of archosauromorph reptile known from England. The type species of Rhombopholis is Rhombopholis scutulata. Specimens of this genus were collected from the Leamington quarry, near Warwick. This locality belongs to the Bromsgrove Sandstone Formation, which is dated to the Anisian age of the Middle Triassic, approximately 245 million years ago.
Dinocephalosauridae is an extinct clade of marine and terrestrial archosauromorph reptiles that lived throughout the Triassic period. Like tanystropheids, they are characterized by their long necks, lengthened by either addition of cervical vertebrae or elongation of the individual bones.
Luopingosaurus is an extinct genus of pachypleurosaurid sauropterygian from the Middle Triassic Guanling Formation of Yunnan Province, China. The genus contains a single species, L. imparilis, known from a well-preserved, nearly complete skeleton.
Gracilicollum is an extinct genus of likely tanystropheid archosauromorph from the Middle Triassic (Anisian) Guanling Formation of China. The genus contains a single species, G. latens, known from a skull and partial neck.
Luxisaurus is an extinct genus of tanystropheid archosauromorph reptile from the Middle Triassic (Anisian) Guanling Formation of China. The genus contains a single species, L. terrestris, known from an articulated partial skeleton. Luxisaurus is hypothesized to have lived a more terrestrial lifestyle than many other tanystropheids, which may have been aquatic.
