Tanystropheidae is an extinct

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of mostly marine

archosauromorph Archosauromorpha ( Greek for "ruling lizard forms") is a clade of diapsid reptiles containing all reptiles more closely related to archosaurs (such as crocodilians and dinosaurs, including birds) rather than lepidosaurs (such as tuataras, li ...

reptiles that lived throughout the

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

Period. They are characterized by their long, stiff necks formed from elongated

cervical vertebrae In tetrapods, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In ...

with very long

cervical rib A cervical rib in humans is an extra rib which arises from the seventh cervical vertebra. Their presence is a congenital abnormality located above the normal first rib. A cervical rib is estimated to occur in 0.2% to 0.5% (1 in 200 to 500) of th ...

s. Some tanystropheids such as ''

Tanystropheus ''Tanystropheus'' (Greek ~ 'long' + 'hinged') is an extinct archosauromorph reptile from the Middle and Late Triassic epochs. It is recognisable by its extremely elongated neck, which measured long—longer than its body and tail combined. T ...

'' had necks that were several meters long, longer than the rest of their bodies. Tanystropheids are known from

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...

(

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eigh ...

, China, and

Saudi Arabia Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the List of Asian countries by area, fifth-largest country in Asia ...

), North America and probably

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the souther ...

(

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

). The presence of tanystropheids in Europe and China indicate that they lived along much of the coastline of the

Tethys Ocean The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean that covered most of the Earth during much of the Mesozoic Era and early Cenozoic Era, located between the ancient continents ...

. However, species in western North America are found in terrestrial deposits, suggesting that as a group, tanystropheids were ecologically diverse. Relationships among tanystropheid species have been difficult to resolve because most specimens were flattened during fossilization and are preserved two-dimensionally. Three-dimensional fossils are known from Europe and North America.

Phylogeny

2021 File:2021 collage V2.png, From top left, clockwise: the James Webb Space Telescope was launched in 2021; Protesters in Yangon, Myanmar following the coup d'état; A civil demonstration against the October 2021 coup in Sudan; Crowd shortly after t ...

, a phylogenetic study was conducted by S. Spiekman, N. Fraser, and T. Schayer in an attempt to clarify the systematics of "

protorosaur Protorosauria is an extinct polyphyletic group of archosauromorph reptiles from the latest Middle Permian (Capitanian stage) to the end of the Late Triassic (Rhaetian stage) of Asia, Europe and North America. It was named by the English anatom ...

" groups. A total of 16 individual trees were found using different character scoring methods and unstable

OTU Otu or OTU may refer to: * Otu: ** Otu, Iran, a village in Mazandaran Province, Iran ** Otu, Siga, Japan ** Otú Airport, an airport in the village of Otú and serving the town of Remedios, Colombia * OTU: ** Ontario Tech University, a postsecond ...

exclusions. The results of analysis 3A, with ratio and ordered characters treated as such and pruning 5 out of 40 OTUs ''a posteriori'' to offer maximum resolution/minimum polytomies, are shown:

List of genera

*''

Amotosaurus ''Amotosaurus'' is an extinct genus of tanystropheid protorosaur from the earliest Middle Triassic (early Anisian stage) of Black Forest, southwestern Germany. ''Amotosaurus'' is known from the holotype SMNS 50830, a partial skeleton includ ...

'' *''

Augustaburiania ''Augustaburiania'' is an extinct genus of tanystropheid archosauromorph from the latest Early Triassic (late Olenekian stage) of Volgograd Region, western Russia. All specimens were recovered in the right slope of the Don River valley from th ...

'' *''

Cosesaurus ''Cosesaurus'' is a genus of archosauromorph reptiles likely belonging to the family Tanystropheidae. It is known from fossil imprints of a single small skeleton, MGB V1, which was found in Muschelkalk outcrops near the municipalities of Mon ...

'' *''

Elessaurus ''Elessaurus'' is an extinct genus of archosauromorph from the Early Triassic of Brazil. It contains a single species, ''Elessaurus gondwanoccidens''. It possessed a variety of features common to basal archosauromorphs, particularly basal tanyst ...

''? *''

Dinocephalosaurus ''Dinocephalosaurus'' (meaning "terrible-headed reptile") 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 ...

'' *''

Exilisuchus ''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'' assemb ...

''? *''

Fuyuansaurus ''Fuyuansaurus'' is an extinct genus of "protorosaur" reptiles (probably part of Tanystropheidae) known from the Middle Triassic (Ladinian stage) Falang Formation of southern China. ''Fuyuansaurus'' was first named by Nicholas C. Fraser, Olivi ...

'' *''

Gwyneddosaurus ''Gwyneddosaurus'' is a possibly invalid genus of extinct aquatic tanystropheid reptile. The type species, ''G. erici'' was described in 1945 by Wilhelm Bock, who identified it as a coelurosaurian dinosaur related to '' Podokesaurus'' (at the ...

'' (possible chimera of ''Tanytrachelos'' and a

coelacanth The coelacanths ( ) are fish belonging to the order Actinistia that includes two extant species in the genus '' Latimeria'': the West Indian Ocean coelacanth (''Latimeria chalumnae''), primarily found near the Comoro Islands off the east c ...

; thus ''Gwyneddosaurus'' is a possible senior synonym of ''Tanytrachelos'') *''

Langobardisaurus ''Langobardisaurus'' (, meaning Reptile of Langobardi, in reference to the Long Bearded People, an ancient Italian civilization) is an extinct genus of tanystropheid archosauromorph reptile, with one known species, ''L. pandolfii''. Its fossi ...

'' *''

Macrocnemus ''Macrocnemus'' is an extinct genus of archosauromorph reptile known from the Middle Triassic (Late Anisian to Ladinian) of Europe and China. ''Macrocnemus'' is a member of the Tanystropheidae family and includes three species''. Macrocnemus ...

'' *''

Ozimek Ozimek (german: Malapane; szl, Uoźimek) is a town in Opole County, Opole Voivodeship, Poland, with 8,657 inhabitants (2019). History Ozimek dates back to an early modern settlement. It was named both ''Ozimek'' and ''Małapanew'', with bot ...

''? *''

Pectodens ''Pectodens'' (meaning "comb tooth") 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 ...

'' *''

Protanystropheus ''Protanystropheus'' is an extinct genus of archosauromorph from the Middle Triassic (Anisian stage) of Poland, Germany, Austria and the Netherlands. It was named by Sennikov in 2011 and the type species is ''Protanystropheus antiquus'', first ...

'' *''

Raibliania ''Raibliania'' is an extinct genus of Tanystropheidae, tanystropheid Archosauromorpha, archosauromorph discovered in the Calcare del Predil Formation in Italy. It lived during the Carnian stage of the Late Triassic and it was related to ''Tanystr ...

'' *'' Sclerostropheus'' *''

Sharovipteryx ''Sharovipteryx'' ("Sharov's wing", known until 1981 as ''Podopteryx'', "foot wing"), is a genus of early gliding reptiles containing the single species ''Sharovipteryx mirabilis''. It is known from a single fossil and is the only glider with a m ...

''? *''

'' *''

Tanytrachelos ''Tanytrachelos'' is an extinct genus of tanystropheid archosauromorph reptile from the Late Triassic of the eastern United States. It contains a single species, ''Tanytrachelos ahynis'', which is known from several hundred fossil specimens pres ...

References

Tanystropheids Prehistoric reptile families Triassic reptiles Triassic first appearances Triassic extinctions Taxa named by Paul Gervais {{triassic-reptile-stub