All Topics  
Cynognathus

 

   Email Print
   Bookmark   Link






 

Cynognathus



 
 
Cynognathus was a metre-long predator of the Lower Triassic
Triassic

The Triassic is a geologic period that extends from about 251 to 199 annum . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic....
. It was one of the more mammal
Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
-like of the "mammal-like reptiles", a member of a grouping called Eucynodontia
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 genus
Genus

A genus is a low-level taxonomic rank used in the classification of living and fossil organisms. The taxonomic ranks are domain , kingdom , phylum, class , order , family , genus, and species....
 Cynognathus had an almost worldwide distribution. Fossil
Fossil

Fossils are the preserved remains or trace fossil of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous Rock formations and sedimentary rock layers is known as the fossil record....
s have so far been recovered from South Africa
South Africa

The Republic of South Africa, also known by Official names of South Africa, is a country located at the southern tip of the continent of Africa....
, South America
South America

South America is the southern continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere....
, China
China

China is a Culture of China, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
 and Antarctica
Antarctica

Antarctica is Earth's southernmost continent, overlying the South Pole. It is situated in the Antarctica of the southern hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean....
.

genus Cynognathus ("Dog jaw") has been given several different names over the years. It has also been known as Cistecynodon, Cynidiognathus, Cynogomphius, Karoomys, Lycaenognathus, Lycochampsa, Lycognathus, and Nythosaurus.






Discussion
Ask a question about 'Cynognathus'
Start a new discussion about 'Cynognathus'
Answer questions from other users
Full Discussion Forum



Encyclopedia


Cynognathus was a metre-long predator of the Lower Triassic
Triassic

The Triassic is a geologic period that extends from about 251 to 199 annum . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic....
. It was one of the more mammal
Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
-like of the "mammal-like reptiles", a member of a grouping called Eucynodontia
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 genus
Genus

A genus is a low-level taxonomic rank used in the classification of living and fossil organisms. The taxonomic ranks are domain , kingdom , phylum, class , order , family , genus, and species....
 Cynognathus had an almost worldwide distribution. Fossil
Fossil

Fossils are the preserved remains or trace fossil of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous Rock formations and sedimentary rock layers is known as the fossil record....
s have so far been recovered from South Africa
South Africa

The Republic of South Africa, also known by Official names of South Africa, is a country located at the southern tip of the continent of Africa....
, South America
South America

South America is the southern continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere....
, China
China

China is a Culture of China, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
 and Antarctica
Antarctica

Antarctica is Earth's southernmost continent, overlying the South Pole. It is situated in the Antarctica of the southern hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean....
.

Names

The genus Cynognathus ("Dog jaw") has been given several different names over the years. It has also been known as Cistecynodon, Cynidiognathus, Cynogomphius, Karoomys, Lycaenognathus, Lycochampsa, Lycognathus, and Nythosaurus. In addition, according to the records of the Peabody Museum of Natural History at Yale
Yale University

Yale University is a private university in New Haven, Connecticut. Founded in 1701 as the Collegiate School, Yale is the Colonial Colleges institution of higher education in the United States and is a member of the Ivy League....
, Richard Owen
Richard Owen

Sir Richard Owen Order of the Bath was an English people biologist, comparative anatomy and paleontology.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. 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
Mesozoic

The Mesozoic Era is one of three Geologic time scale of the Phanerozoic eon . The division of time into eras dates back to Giovanni Arduino, in the 18th century, although his original name for the era now called the 'Mesozoic' was 'Secondary' ....
 creature might be regarded as excessive, but it's by no means a record. The dinosaur Plateosaurus
Plateosaurus

Plateosaurus is a genus of Plateosauridae prosauropoda dinosaur that lived during the Norian and Rhaetian stages of the Late Triassic Period , around 216 to 199 annum in what is now Europe....
 engelhardti
, has been named well over 20 times.

The genera Karoomys, Cistecynodon and Nythosaurus are known only from tiny juveniles, while Lycognathus cucullatus seems to be a misidentified snake
Snake

Snakes are elongate legless carnivore reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears....
 from the Balearic Islands
Balearic Islands

The Balearic Islands are an archipelago in the western Mediterranean Sea, near the eastern coast of the Iberian Peninsula.The four largest islands are Majorca, Minorca, Ibiza, and Formentera....
, although confirmation is elusive.

Fossil locations

Snider Pellegrini Wegener Fossil Map
Fossils have been found in Karoo
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 Puesto Viejo Formation; Fremouw Formation
Mount Kirkpatrick Formation

File:Cryolophosaurus jconway.jpgThe 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

Lesotho , officially the Kingdom of Lesotho, is a landlocked country and enclave ? entirely surrounded by the South Africa. Formerly Basutoland, it is a member of the Commonwealth of Nations....
; Argentina
Argentina

Argentina, officially the Argentine Republic , is a country in South America, constituted as a federation of 23 provinces and an autonomous city....
; Antarctica; and China.

Age

Cynognathus lived between the Spathian (Lower Triassic) and the Anisian (Middle Triassic).

Description


Cynognathus was a heavily built animal, and measured around in body length. It had a particularly large head, in length, with wide jaws and sharp teeth. Like 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
Secondary palate

The secondary palate is an anatomical structure that divides the nasal cavity from the mouth 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
Nerve

A nerve is an enclosed, cable-like bundle of Peripheral nervous system axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons....
s and blood vessels. In mammals, such structures allow hairs (whiskers
Vibrissae

Vibrissae , or whiskers, are specialized hairs, usually employed for tactile sensation, but can also refer to the stiff feathers near the mouths of some birds....
) to be used as sensory organs.

All of these features indicate that Cynognathus was an endotherm
Endotherm

Endotherm may refer to:*warm-blooded organism*endothermic processSee also*ectotherm...
ic animal: a "warm blooded" creature with a relatively high metabolic
Metabolism

Metabolism is the set of chemical reactions that occur in living organisms in order to maintain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments....
 rate, which needed to be able to process food and oxygen
Oxygen

Oxygen no O2 produced; 2) O2 produced, but absorbed in oceans & seabed rock; 3) O2 starts to gas out of the oceans, but is absorbed by land surfaces and formation of ozone layer; 4-5) O2 sinks filled and the gas accumulates]]...
 quickly.

See also

  • Thrinaxodon
    Thrinaxodon

    Thrinaxodon was a cynodont, a cat-sized therapsid. Pits on the skull indicate that Thrinaxodon had Vibrissae and, therefore probably also had a covering of fur....
  • Tritylodontids
    Tritylodontidae

    Tritylodontids were small to medium-sized, highly specialized and extremely mammal-like cynodonts. They were the last family of the non-mammalian synapsids....
  • Cynognathia
    Cynognathia

    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....
  • Evolution of mammals
    Evolution of mammals

    __FORCETOC__The evolution of mammals from synapsids was a gradual process which took approximately 70 million years, beginning in the mid-Permian....