The Donguz Formation, Donguz Svita, or Donguz Rocks (russian: Донгузские скалы) is a

Middle Triassic In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between Ma and ...

geological formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

that crops out on the right bank of Donguz River in

Orenburg Oblast Orenburg Oblast (russian: Оренбургская область, ''Orenburgskaya oblast'') is a federal subject of Russia (an oblast). Its administrative center is the city of Orenburg. From 1938 to 1957, it bore the name ''Chkalov Oblast'' () ...

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

, across the settlement of Pervomaisky. The formation is equivalent to a

biostratigraphic Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them.Hine, Robert. “Biostratigraphy.” ''Oxford Reference: Dictionary of Bio ...

unit, the Donguz

Gorizont Gorizont (russian: Горизонт, ''Horizon''), GRAU index 11F662, is a series of 35 Russian, previously Soviet, geosynchronous communications satellites launched between 1978 and 2000. The programme was started in order to develop a satelli ...

. It is famous for its rich collection of the

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s of Middle Triassic

tetrapod Tetrapods (; ) are four-limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant and extinct amphibians, sauropsids ( reptiles, including dinosaurs and therefore birds) and synapsids (pelycosaurs, extinct theraps ...

s. It is a

nature monument A natural monument is a natural or natural/cultural feature of outstanding or unique value because of its inherent rarity, representative of aesthetic qualities or cultural significance. Under World Commission on Protected Areas guidelines, nat ...

(особо охраняемых природных территорий (ООПТ)).Uraloved.ru
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Fossil content

The following fossils have been found in the Donguz Formation: *

Temnospondyls Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carb ...

** '' Eryosuchus antiquus'', Ochev ** '' E. garjainovi'', Ochev ** '' E. tverdochlebovi'', Ochev ** ''

Bukobaja ''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 "''Mastodons ...

''? sp. ** '' Plagiorophus danilovi'' ** '' Plagioscutum ochevi'', Shishkin ** '' Plagiosternum paraboliceps'' (Konzhukova) *

Thecodont Thecodontia (meaning 'socket-teeth'), now considered an obsolete taxonomic grouping, was formerly used to describe a diverse "order" of early archosaurian reptiles that first appeared in the latest Permian period and flourished until the end of th ...

s ** '' Jushatyria vjushkovi'' *

Procolophonid Procolophonidae is an extinct family of small, lizard-like parareptiles known from the Late Permian to Late Triassic that were distributed across Pangaea, having been reported from Europe, North America, China, South Africa, South America, Antarc ...

** '' Kapes serotinus'', Novikov *

Proterosuchid Proterosuchidae is an early family of basal archosauriforms whose fossils are known from the Latest Permian and the Early Triassic of Europe, Asia, Africa, Australia and possibly South America. The name comes from Greek πρότερο- ("first") ...

s ** '' Sarmatosuchus ochevi'', Sennikov *

Erythrosuchid Erythrosuchidae (meaning "red crocodiles" in Greek) are a family of large basal archosauriform carnivores that lived from the later Early Triassic (Olenekian) to the early Middle Triassic (Anisian). Naming The family Erythrosuchidae was named b ...

s ** '' Uralosaurus magnus'', (Ochev) *

Rauisuchidae Rauisuchidae is a group of large (up to or more) predatory Triassic archosaurs. There is some disagreement over which genera should be included in Rauisuchidae and which should be in the related Prestosuchidae and Poposauridae, and indeed wheth ...

** '' Dongusia colorata'', Huene ** '' Vjushkovisaurus berdjanensis'', Ochev *

Euparkeriidae Euparkeriidae is an extinct family of small carnivorous archosauriforms which lived from the Early Triassic to the Middle Triassic (Anisian). While most other early archosauriforms walked on four limbs, euparkeriids were probably facultative ...

** '' Dorosuchus neoetus'', Sennikov *

Dicynodonts Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were Herbivore, herbivorous animals with a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horn ...

** ''

Kannemeyeria ''Kannemeyeria'' is a genus of dicynodont that lived during the Anisian age of Middle Triassic period in what is now Africa and South America. The generic name is given in honor of Dr. Daniel Rossouw Kannemeyer, the South African fossil collect ...

'' spp. * ''

Shansiodon ''Shansiodon'' is a genus of dicynodont from Middle Triassic (Anisian and Ladinian) of China and South Africa (sp. indet.). Dicynodonts Anisian life Middle Triassic synapsids of Africa Triassic South Africa Fossils of South Africa Triassic sy ...

'' (''

Rhinodicynodon ''Rhinodicynodon'' is an extinct genus of dicynodont therapsid of the Middle Triassic (Anisian) Donguz Formation of European Russia.Therocephalian Therocephalia is an extinct suborder of eutheriodont therapsids (mammals and their close relatives) from the Permian and Triassic. The therocephalians ("beast-heads") are named after their large skulls, which, along with the structure of their te ...

s ** '' Dongusaurus schepetovi'', Vyushkov ** '' Nothogomphodon danilovi'', Tatarinov *

Diademodontid Diademodontidae is an extinct family of Triassic gomphodonts. The best-known genus is ''Diademodon'' from South Africa. ''Titanogomphodon'' from Namibia may also be a member of Diademodontidae. The Chinese genera ''Hazhenia'' and ''Ordosiodon'' ha ...

s ** '' Scalenodon boreus'', Tatarinov *

Traversodontid Traversodontidae is an extinct family of herbivorous cynodonts. Traversodonts were primarily Gondwanan, with many species known from Africa and South America. Recently, traversodonts have also been found from Europe and eastern North America. Tra ...

s ** '' Antecosuchus ochevi'', Tatarinov *

Therapsid Therapsida is a major group of eupelycosaurian synapsids that includes mammals, their ancestors and relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more ...

s ** '' Calleonasus furvus'' ** '' Cristonasus koltaeviensi'' ** '' Elatosaurus facetus'' ** '' Nasoplanites danilovi'' ** '' Parvobestiola bashkiriensis'' ** '' Rabidosaurus cristatus'' ** '' Rhadiodromus klimovi'' *

Fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

** '' Ceratodus bucobaensis'', '' C. recticristatus'' *

Archosaurs Archosauria () is a clade of diapsids, with birds and crocodilians as the only living representatives. Archosaurs are broadly classified as reptiles, in the cladistic sense of the term which includes birds. Extinct archosaurs include non-avi ...

** '' Dongusuchus efremovi'', Sennikov

References

{{Reflist Geologic formations of Russia Triassic System of Europe Triassic Russia Anisian Stage Sandstone formations Shale formations Conglomerate formations Fluvial deposits Deltaic deposits Paleontology in Russia Formations

Fossil content

See also

References