Parotosuchus is an extinct genus of capitosaurian temnospondyls within the family Mastodonsauridae. Fossils are known from the Early Triassic of Europe, Africa, Australia, and Antarctica. It was about 2 metres (6.6 ft) long and likely lived in aquatic environments such as lakes and rivers. Parotosuchus was covered in a scaly skin, unlike the smooth skin of modern-day amphibians, and probably moved with an eel-like motion in the water.
Wetlugasaurus is an extinct genus of temnospondyl from the Early Triassic (Olenekian) Charkabozh, Kzylsaiskaya, Petropavlovka, Kamennyi Yar and Vetluga Series Formations of northern Russia and Greenland. It had a 22 centimetres (8.7 in) long skull, and reached a total length of 1 metre.
Bystrowiana is an extinct genus of bystrowianid chroniosuchian from upper Permian deposits of Vladimir Region, Russia and Jiyuan, China. Chroniosuchians are often thought to be reptiliomorphs, but some recent phylogenetic analyses suggest instead that they are stem-tetrapods. The genus is named in honour of the Russian paleontologist Alexey Bystrow. It was first described by Vyushkov in 1957 and the type species is Bystrowiana permira. Two species—B. permira and B. sinica—are known.
Bukobaja is an extinct genus of mastodonsaurid temnospondyl from the middle Triassic of Russia. It contains a single species, Bukobaja enigmatica. Bukobaja mainly occurs in the Bukobay Svita as part of the Ladinian?-age "Mastodonsaurus fauna", a section of Russian Triassic biostratigraphy characterized by "Mastodonsaurus" torvus. It was also present in the underlying Donguz Svita. Bukobaja appears to be a valid genus similar to, yet distinct from, Mastodonsaurus. Despite appearing to possess several unique features, Bukobaja is still known from very few remains. This has led to difficulties in determining its relations more precisely than "Mastodonsauridae incertae sedis". It has also been compared to trematosaurids.
Inflectosuchus is an extinct genus of prehistoric amphibian.
Yarengia is an extinct genus of temnospondyl amphibian in the superfamily Mastodonsauroidea. It is known from Yarenga River, representing the Triassic of Russia.
Thoosuchus is an extinct genus of basal trematosauroid trematosaurian temnospondyl. Fossils have been found from Russia and date back to the Early Triassic. It is the type genus of the family Thoosuchidae, formerly called the subfamily Thoosuchinae and placed within Benthosuchidae. The benthosuchids were originally composed of the majority of basal trematosaurian forms regarded as the ancestors of the trematosaurids.
Malutinisuchus is an extinct genus of Archosauromorph. The genus was named in 1986 with the description of the type species M. gratus. Malutinisuchus is known from Ladinian-age Middle Triassic deposits in the Bukobay and Rassypnaya localities in Orenburg Oblast, Russia. In Russia, deposits of this age are referred to the Bukobay Gorizont.
Bystrowiella is an extinct genus of bystrowianid chroniosuchians from upper Middle Triassic deposits of Kupferzell and Vellberg, northern Baden-Württemberg, Germany.
Vladlenosaurus is an extinct genus of capitosaurian temnospondyl from Russia. It lived during the late Vetlugian. Based on the type of deposits it was found in, Vladlenosaurus probably inhabited lacustrine, or lake, habitats. The type species is V. alexeyevi, named in 2000.
Axitectum is an extinct genus of bystrowianid chroniosuchians from lower Triassic deposits of Nizhni Novgorod and Kirov Regions, Russia. It was a rather large animal judging by the size of its vertebrae. The back was covered in bands of highly ornamented osteoderm plates, similar to those found in modern crocodiles. The bands overlapped with the next band at the posterior end.
Dromotectum is an extinct genus of bystrowianid chroniosuchians from the Late Permian of China and Early Triassic of Russia. Two species have been named: the type species D. spinosum and the species D. largum. D. spinosum, the first species to be named, comes from Lower Triassic deposits in the Samara Region of European Russia and is known from the holotype PIN 2424/23, which consists of armor scutes, and from PIN 2424/65, 4495/14 and 2252/397. It was found in the Staritskaya Formation of the Rybinskin Horizon and named by I.V. Novikov and M.A. Shishkin in 2000. The generic name means “corridor with hipped vault” + “roof” (tecton), and the specific name means “spinous”. A second species, D. largum, was named by Liu Jun, Xu Li, Jia Song-Hai, Pu Han-Yong, and Liu Xiao-Ling in 2014 from the Shangshihezi Formation near Jiyuan in Henan province, China on the basis of specimen IVPP V 4013.1, a large scute.
Vonhuenia is an extinct genus of proterosuchid, a basal archosauriform from the Early Triassic of Russia. Fossils have been found in the Vokhminskaya Formation, along the Vetluga River that are Induan in age, making Vonhuenia one of the earliest archosauriforms.
Blomosuchus is an extinct genus of archosauriform from the Early Triassic of Russia. The type species was named in 1992 as Blomia georgii. However, the name Blomia was preoccupied by a genus of mites in the family Glycyphagidae (Blomia), so the genus was renamed Blomosuchus in 1997. Fossils of Blomosuchus have been found along the Vetluga River besides fossils of another problematic archosauriform, Vonhuenia.
Exilisuchus is an extinct genus of archosauromorph reptile from the Early Triassic of Russia. The type species E. tubercularis was named in 1979. Fossils are known from two Russian assemblages, the Benthosuchus - Thoosuchus assemblage and the Angusaurus assemblage. Both are Olenekian in age. Although initially believed to be a proterosuchid archosauriform, a 2016 analysis found that it also shared features with tanystropheids, and thus is currently classified as Archosauromorpha incertae sedis. Due to the small amount of preserved material, this genus is sometimes considered a nomen dubium.
Bystrowianidae is a family of chroniosuchian tetrapods from the Permian and Triassic periods.
The Yarenskian Gorizont is a major biostratigraphic unit in Russia corresponding to Upper Olenekian-age terrestrial sediments. It lies above the Ustmylian Gorizont of the Vetlugian Supergorizont, and is located below a short unconformity overlain by the Donguz Gorizont. Some paleontologists elevate the Yarenskian to a supergorizont and subdivide it into two smaller units: the older Fedorovskian Gorizont and the younger Gamskian Gorizont. Others prefer to consider the Fedorovskian and Gamskian to be subgorizonts or members of the Yarenskian. Vertebrate index fossils of the Fedorovskian include the lungfish Gnathorhiza, the trematosaurid Inflectosaurus, and the procolophonid Burtensia. In the Gamskian, these index fossils are replaced by Ceratodus, Trematosaurus, and Kapes, respectively. The Yarenskian as a whole is characterized by the capitosaur amphibian Parotosuchus, and has also been known as the Parotosuchus fauna. A few geographical influence on the faunas can be observed; erythrosuchids and rhytidosteids are more common in southern exposures while procolophonids and putative "rauisuchids" are more common in the north.
The Ustmylian Gorizont is a Lower Triassic biostratigraphic unit in Western Russia. The Ustmylian Gorizont is the youngest subunit of the Vetlugian Supergorizont, lying above the Sludkian Gorizont and below the Yarenskian Gorizont. It corresponds to the later part of the early Olenekian stage. Along with the Sludkian Gorizont, the Ustmylian Gorizont is encompassed by the "Wetlugasaurus fauna", named after a capitosaur amphibian index fossil. While the Sludkian is characterized by Wetlugasaurus angustifrons, the Ustmylian is characterized by Wetlugasaurus malachovi.
The Sludkian Gorizont is a Lower Triassic biostratigraphic unit in Western Russia. The Sludkian Gorizont is a part of the Vetlugian Supergorizont and corresponds to the middle part of the early Olenekian stage, lying above the Rybinskian Gorizont and below the Ustmylian Gorizont. The Sludkian and Ustmylian Gorizonts are together encompassed by the "Wetlugasaurus fauna", named after a capitosaur amphibian index fossil. The Sludkian is characterized by Wetlugasaurus angustifrons, while the Ustmylian is characterized by Wetlugasaurus malachovi.
The Rybinskian Gorizont is a Lower Triassic biostratigraphic unit in Western Russia. It is a part of the Vetlugian Supergorizont and corresponds to the earliest part of the Olenekian stage, lying above the late Induan-age Zaplavnian Horizon and below the Sludkian Gorizont. The Rybinskian Gorizont is sometimes known as the Benthosuchus fauna, due to abundant fossils of Benthosuchus, a temnospondyl amphibian index fossil. Related amphibians such as Thoosuchus also increase in abundance, and the interval additionally hosts the oldest fossils of procolophonines and putative true archosaurs in the region.
