Therocephalia
Moschorhinus
- Southern Africa
- Russia
- China
- Antarctic
The Therocephalia are an extinct group of terrestrial vertebrates from the group of therapsids ( " mammal -like reptiles "). They first appeared in fossil deposits of South Africa from the Middle Permian. On the form they were richest in Upper Permian, from the present findings from southern Africa, Russia and China. In the Triassic, they were rare. Finds there is, inter alia, from the Lower and Middle Triassic of Antarctica.
The Therocephalia were great, mainly predatory meat or small insectivores. Some of Triassic forms such as Bauria from South Africa were living herbivores.
Features
Therocephalier had a relatively large, massive and long, but relatively low skull. The snout was wide, trimmed with large canines and simple, conical molars, but also could be missing.
The jaw muscles ranged up on the cranium and left between the two upward skull windows only a narrow sagittal crest formed by the parietal bones left. This is the main difference between the skulls of the gorgonopsians. Some Therocephaliaformen had a fully developed secondary palate, a characteristic which they share with the Cynodonten, but because of differences in detail exist, evolved independently of them. Cranial window and orbit could flow together. The cheekbone was never wide.
The lumbar vertebrae were small, thin ribs. The ilium had finger-like extensions at its back end. Her limbs were long. Some forms had mammal- like body proportions and a strong back- formed cock. The Phalangenformel was 2.3.3.3.3 and thus corresponds to that of mammals.
System
Kuhn is for Therocephalia to seven families and 55 genera and for the Bauriamorphen another 9 families and 45 genera. The early Therocephalia were originally classified as Pristerognathidae, but later recognized as a paraphyletic group and divided into the kurzschnauzigen Lycosuchidae and langschnauzigen Scylacosauridae. Another former Therocephalenfamilie that Scaloposauridae were composed mainly of juvenile specimens of different genera. All further developed Therocephalenformen form the taxon Eutherocephalia, including the hyena -like Whaitsiidae and herbivory Baurioidea.
- Lycosuchidae
- Scylacosauridae
- Eutherocephalia Whaitsiidae
- Moschorhinidae ( = Euchambersiidae )
- Baurioidea