was a meter-long predator
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
of the Early to Middle Triassic
The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...
. It was among the more mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
-like of the Synapsids, a member of a grouping called Eucynodontia
Eucynodontia is a grouping of animals that includes both mammals, such as dogs, and mammal-like non-mammalian therapsids such as cynodonts . Its membership was and is made up of both carnivores and herbivores. The chronological range extends from at least the Lower Triassic, possibly the Upper...
. The 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...
had an almost worldwide distribution. Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s have so far been recovered from South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
The genus Cynognathus
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
, meaning "dog jaw") has been given several different names over the years. It has also been known as Cistecynodon
, and Nythosaurus
. In addition, according to the records of the Peabody Museum of Natural History at Yale
Yale University is a private, Ivy League university located in New Haven, Connecticut, United States. Founded in 1701 in the Colony of Connecticut, the university is the third-oldest institution of higher education in the United States...
, Richard Owen
Sir Richard Owen, FRS KCB was an English biologist, comparative anatomist and palaeontologist.Owen is probably best remembered today for coining the word Dinosauria and for his outspoken opposition to Charles Darwin's theory of evolution by natural selection...
used the name Nythosaurus
for this animal in 1876. This usage seems to be unconnected with Cynognathus
is presently the only recognized member of family Cynognathidae
. Opinions vary as to whether all remains belong to the same species.
The species Cynognathus crateronotus
is also known as Cistecynodon parvus
, Cynidiognathus broomi
, Cynidiognathus longiceps
, Cynidiognathus merenskyi
, Cynognathus beeryi
, Cynognathus minor
, Cynognathus platyceps
, Cynogomphius berryi
, Karoomys browni
, Lycaenognathus platyceps
, Lycochampsa ferox
, Lycognathus ferox
, Nythosaurus browni
. Fifteen different names for one Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...
creature might be regarded as excessive, but it's by no means a record. The dinosaur Plateosaurus
Plateosaurus is a genus of plateosaurid dinosaur that lived during the Late Triassic period, around 216 to 199 million years ago, in what is now Central and Northern Europe. Plateosaurus is a basal sauropodomorph dinosaur, a so-called "prosauropod"...
, has been named well over 20 times.
The genera Karoomys
are known only from tiny juveniles, while Lycognathus cucullatus
seems to be a misidentified snake
Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...
from the Balearic Islands
The Balearic Islands are an archipelago of Spain in the western Mediterranean Sea, near the eastern coast of the Iberian Peninsula.The four largest islands are: Majorca, Minorca, Ibiza and Formentera. The archipelago forms an autonomous community and a province of Spain with Palma as the capital...
, although confirmation is elusive.
Fossils have been found in Karoo
The Karoo is a semi-desert region of South Africa. It has two main sub-regions - the Great Karoo in the north and the Little Karoo in the south. The 'High' Karoo is one of the distinct physiographic provinces of the larger South African Platform division.-Great Karoo:The Great Karoo has an area of...
; the Puesto Viejo Formation; Fremouw Formation
The Mount Kirkpatrick Formation is one of only two major dinosaur-bearing rock formations yet found on the continent of Antarctica; the other is the Santa Marta Formation from the Late Cretaceous...
, in South Africa/Lesotho
Lesotho , officially the Kingdom of Lesotho, is a landlocked country and enclave, surrounded by the Republic of South Africa. It is just over in size with a population of approximately 2,067,000. Its capital and largest city is Maseru. Lesotho is a member of the Commonwealth of Nations. The name...
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
; Antarctica; and China
lived between the Spathian (Lower Triassic) and the Anisian (Middle Triassic).
was a heavily built animal, and measured around 1 metres (3.3 ft) in body length. It had a particularly large head, 30 centimetre (0.984251968503937 ft) in length, with wide jaws and sharp teeth. Its hind limbs were placed directly beneath the body, as in mammals, but the fore-limbs sprawled outwards in a reptilian fashion.
The dentary was equipped with differentiated teeth that show this animal could effectively process its food before swallowing. The presence of a secondary palate
The secondary palate is an anatomical structure that divides the nasal cavity from the oral cavity in many vertebrates.In human embryology, it refers to that portion of the hard palate that is formed by the growth of the two palatine shelves medially and their mutual fusion in the midline...
in the mouth indicates that Cynognathus
would have been able to breathe and swallow simultaneously.
The lack of ribs in the stomach region suggests the presence of an efficient diaphragm: an important muscle for mammalian breathing. Pits and canals on the bone of the snout indicate concentrations of nerve
A peripheral nerve, or simply nerve, is an enclosed, cable-like bundle of peripheral axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons. Nerves are found only in the peripheral nervous system...
s and blood vessels. In mammals, such structures allow hairs (whiskers) to be used as sensory organs.
Thrinaxodon was a cynodont, an ermine-sized therapsid. Pits on the skull suggest that Thrinaxodon may have had whiskers, and by extension a protective covering of fur. There are suggestions that it was warm-blooded...
Tritylodontids were small to medium-sized, highly specialized and extremely mammal-like cynodonts. They were the last family of the non-mammalian synapsids. One of the last cynodont lines to appear, the Tritylodontidae descended from a Cynognathus-like cynodont...
The Cynognathians are one of the two major clades of the infraorder Eucynodontia, the other being the Probainognathians. Cynognathus, the most basal representative of the clade was a carnivore, unlike most cynognathians. The cynognathians were mostly mammal-like, but the subgroup Tritylodontids...
- Evolution of mammals
__FORCETOC__The evolution of mammals within the synapsid lineage was a gradual process that took approximately 70 million years, beginning in the mid-Permian. By the mid-Triassic, there were many species that looked like mammals, and the first true mammals appeared in the early Jurassic...
Paleoworld was a documentary television series that was produced for The Learning Channel, and has had a total of 50 episodes. Some consider it to be the largest and most comprehensive paleontology series ever made. The series began in late September 1994 and, after 4 seasons, ended in 1997...
- Featured in the episode "Tail Of A Sail".
Harry Govier Seeley was a British paleontologist.-Career:Seeley was born in London, the son of Richard Hovill Seeley, goldsmith, and his second wife Mary Govier. He attended classes at the Royal School of Mines, Kensington before becoming an assistant to Adam Sedgwick at the Woodwardian Museum,...
(1895), "Researches on the structure, organization, and classification of the fossil Reptilia. Part IX., Section 5. On the skeleton in new Cynodontia from the Karroo rocks". Phil. Transactions of the Roy. Soc. of London, series B 186, p. 59–148.