Inostrancevia
Encyclopedia
Inostrancevia is a genus of gorgonopsid therapsid found in Sokolki, on the Smaller Northern Dvina River near Kotlas
in Arkhangelsk Oblast
, Russia
. The animal lived 251 million years ago during the Late Permian
. The species I. alexandri is known from an almost complete skeleton missing some minor rib and vertebrae attachments.
As with all other gorgonopsid species, it was a quadruped that had an upright posture of 1-4.3 metres long (as large as a bear), with a bone structure characteristic of strong muscle
attachments. The skull of 45 cm in length contained a smaller eye socket and larger temporal opening than other less advanced therapsids, like Biarmosuchus tener
. The teeth were quite large, the upper palate
containing 6 large incisor
s, 2 large canines and 10 smaller back teeth and the mandible
contained 6 large incisors and 8 smaller incisors.
Kotlas
Kotlas is a town in the southeast of Arkhangelsk Oblast, Russia, situated at the confluence of the Northern Dvina and Vychegda Rivers. Administratively, it is incorporated as a town of oblast significance . It also serves as the administrative center of Kotlassky District, by which it is...
in Arkhangelsk Oblast
Arkhangelsk Oblast
Arkhangelsk Oblast is a federal subject of Russia . It includes the Arctic archipelagos of Franz Josef Land and Novaya Zemlya, as well as the Solovetsky Islands in the White Sea....
, 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...
. The animal lived 251 million years ago during the Late Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
. The species I. alexandri is known from an almost complete skeleton missing some minor rib and vertebrae attachments.
Description
Muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
attachments. The skull of 45 cm in length contained a smaller eye socket and larger temporal opening than other less advanced therapsids, like Biarmosuchus tener
Biarmosuchus
Biarmosuchus tener was a therapsid that lived around 255 mya during the late Permian period. It was discovered in the Perm region of Russia. The specimen was found in channel sandstone that was deposited by flood waters originating from the young Ural mountains. The species is the most primitive of...
. The teeth were quite large, the upper palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
containing 6 large incisor
Incisor
Incisors are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.-Function:...
s, 2 large canines and 10 smaller back teeth and the mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
contained 6 large incisors and 8 smaller incisors.