Tsylmosuchus
Encyclopedia
Tsylmosuchus is an extinct genus
of rauisuchia
n that may be a member of the family
Rauisuchidae
. It is known from the southern Urals region of Russia
. Tsylmosuchus occurred throughout the Olenekian
age of the Early Triassic
. Some of the strata from which Tsylmosuchus has been found are early Olenekian in age, making it one of the earliest archosaur
s. The genus is named after the Tsilma River
, near where fossils have been found. Three species are currently recognized: the type species
T. jakovlevi, T. samariensis, and T. donensis.
. Like several other early rauisuchians such as Energosuchus
and Vytshegdosuchus
, Tsylmosuchus has elongated cervical vertebrae, giving it a relatively long neck.
and Pechora River
s in northern European Russia
. Some material once referred to the proterosuchid Chasmatosuchus magnus
has since been referred to this species.
Two other species were named and described alongside the type. T. samariensis is known from a few vertebrae from the region of Obshchy Syrt
. T. donensis is known only from a cervical vertebra and was thus only tentatively named as a distinct species. It has been found from Donskaya Luka in Volgograd Oblast
.
-Wetlugasaurus
and Parotosuchus
faunas, which are early and late Olenekian in age, respectively. These faunas, known from hundreds of sites throughout eastern Europe, consisted of a wide array of temnospondyls (primarily trematosaurids
), procolophonid
s, and early archosauriforms. These faunas occurred in a large river basin, which likely experienced a trend of increasing humidity during the later part of the Olenekian.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of rauisuchia
Rauisuchia
Rauisuchia is a group of predatory and mostly large Triassic archosaurs. As a clade, Rauisuchia includes these Triassic forms and all crocodylomorphs, which are descendants of Triassic rauisuchians. The group in its traditional sense is paraphyletic, because it does not include crocodylomorph...
n that may be a member of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Rauisuchidae
Rauisuchidae
Rauisuchidae is a group of large predatory Triassic archosaurs, and constitute advanced representatives of the larger group Rauisuchia. There is some disagreement over which genera should be included in the Prestosuchidae, which in Rauisuchidae, and which in the Poposauridae, and indeed whether...
. It is known from the southern Urals region of Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
. Tsylmosuchus occurred throughout the Olenekian
Olenekian
In the geologic timescale, the Olenekian is an age in the Early Triassic epoch or a stage in the Lower Triassic series. It spans the time between 249.7 ± 0.7 Ma and 245 ± 0.7 Ma . The Olenekian follows the Induan and is followed by the Anisian.The Olenekian saw the deposition of a large part of the...
age of the Early Triassic
Early Triassic
The Early Triassic is the first of three epochs of the Triassic period of the geologic timescale. It spans the time between 251 ± 0.4 Ma and 245 ± 1.5 Ma . Rocks from this epoch are collectively known as the Lower Triassic, which is a unit in chronostratigraphy...
. Some of the strata from which Tsylmosuchus has been found are early Olenekian in age, making it one of the earliest archosaur
Archosaur
Archosaurs are a group of diapsid amniotes whose living representatives consist of modern birds and crocodilians. This group also includes all extinct non-avian dinosaurs, many extinct crocodilian relatives, and pterosaurs. Archosauria, the archosaur clade, is a crown group that includes the most...
s. The genus is named after the Tsilma River
Tsilma River
The Tsilma is a river in Leshukonsky District of Arkhangelsk Oblast and Ust-Tsilemsky District of the Komi Republic in Russia. It is a left and one of the main tributaries of the Pechora River. It is long, and the area of its basin...
, near where fossils have been found. Three species are currently recognized: the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
T. jakovlevi, T. samariensis, and T. donensis.
Description
Tsylmosuchus is known primarily from vertebrae. These vertebrae are similar to those of other rauisuchids from East AfricaEast Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
. Like several other early rauisuchians such as Energosuchus
Energosuchus
Energosuchus is an extinct genus of rauisuchian. Fossils are present from the upper Karyomayol and lower Synya formations outcropping along the banks of the Bolshaya Synya River in the Timan-North Urals region in northern European Russia, as well as from the Bukobay Formation in the sothern part...
and Vytshegdosuchus
Vytshegdosuchus
Vytshegdosuchus is a genus of rauisuchid archosaur. It is known from fossil bones discovered from three localities along the Vychegda River in the Komi Republic of the European section of Russia. These fossils were found in rocks of the upper Yarenskian Gorizont, dating to the late Olenekian stage...
, Tsylmosuchus has elongated cervical vertebrae, giving it a relatively long neck.
Species
The type species, T. jakovlevi, was named in 1990. It is known from many vertebrae and a few partial illia collected around the MezenMezen River
The Mezen is a river in Udorsky District of the Komi Republic and in Leshukonsky and Mezensky Districts of Arkhangelsk Oblast in Russia. Its mouth is located in the Mezen Bay of the White Sea. Mezen is one of the biggest rivers of European Russia. It is long, and the area of its basin...
and Pechora River
Pechora River
The Pechora River is a river in northwest Russia which flows north into the Arctic Ocean on the west side of the Ural Mountains. It lies mostly in the Komi Republic but the northernmost part crosses the Nenets Autonomous Okrug. It is 1,809 km long and its basin is 322,000 square kilometers...
s in northern European Russia
European Russia
European Russia refers to the western areas of Russia that lie within Europe, comprising roughly 3,960,000 square kilometres , larger in area than India, and spanning across 40% of Europe. Its eastern border is defined by the Ural Mountains and in the south it is defined by the border with...
. Some material once referred to the proterosuchid Chasmatosuchus magnus
Chasmatosuchus
Not to be confused with Chasmatosaurus.Chasmatosuchus was a large archosauriform reptile from the early Triassic period of South Africa and China. It is one of the earliest well-known archosauriforms. It was over 6 ft long and is thought to have behaved like a modern crocodile...
has since been referred to this species.
Two other species were named and described alongside the type. T. samariensis is known from a few vertebrae from the region of Obshchy Syrt
Obshchy Syrt
Obshchy Syrt is a highland ridge, or plateau , in the european part of Russia. It starts north of Orenburg as a branch of the Ural Mountains and runs in a southwesterly direction to the east bank of the Volga River....
. T. donensis is known only from a cervical vertebra and was thus only tentatively named as a distinct species. It has been found from Donskaya Luka in Volgograd Oblast
Volgograd Oblast
Volgograd Oblast is a federal subject of Russia . Its administrative center is the city of Volgograd. Population: -Geography:*Area: 113,900 km²;*Borders length: 2221,9 km²....
.
Paleobiology
Along with small proterosuchids such as Chasmatosuchus, rauisuchians such as Tsylmosuchus were the top predators in Early Triassic European Russia. Tsylmosuchus was part of what are referred to as the BenthosuchusBenthosuchus
Benthosucus is an extinct genus of temnospondyl amphibian from the Triassic....
-Wetlugasaurus
Wetlugasaurus
Wetlugasaurus is an extinct genus of temnospondyl amphibian from the Early Triassic of northern Russia and Greenland.-References:* The Age of Dinosaurs in Russia and Mongolia by Michael J. Benton, Mikhail A. Shishkin, David M. Unwin, and Evgenii N. Kurochkin. p. 35-59.* Bibliography Of Fossil...
and Parotosuchus
Parotosuchus
Parotosuchus is an extinct genus of capitosauroid temnospondyl within the family Capitosauridae. It was a two-metre-long giant salamander-like predator that lived during the Early Triassic inhabiting lakes and rivers...
faunas, which are early and late Olenekian in age, respectively. These faunas, known from hundreds of sites throughout eastern Europe, consisted of a wide array of temnospondyls (primarily trematosaurids
Trematosauridae
Trematosauridae are a family of large temnospondyl amphibians with many members. They first appeared during the Olenekian stage of the Early Triassic, and existed up until around the Carnian stage of the Late Triassic, although by then they were very rare...
), procolophonid
Procolophonid
The Procolophonids - family Procolophonidae - are a group of small reptiles. Skulls have been discovered, roughly 5 cm in diameter....
s, and early archosauriforms. These faunas occurred in a large river basin, which likely experienced a trend of increasing humidity during the later part of the Olenekian.
External links
- Tsylmosuchus in the Paleobiology DatabasePaleobiology Database' is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.-History:The Paleobiology Database was founded in 2000. It has been funded by the National Science Foundation and the Australian Research Council...