Dicynodont
Tetragonias in the State Museum of Natural History Karlsruhe.
- Worldwide
The Dicynodontia (Greek: "Two - Hundezähner " ) were herbivorous synapsids, which had its heyday from the Middle Permian to the Lower Jurassic. On the Australian continent they survived until the Cretaceous ..
They are found on many continents since their time were the land masses nor the supercontinent Pangaea. Her hull was barrel-shaped, as the animals required as herbivores a relatively long digestive tract. Unlike most reptiles, her tail was very short. Your toothless mouth ended in a horned beak; at the sides of the Dicynodontier had two tusks ( just " dogs" - ie canines, hence the name), which could have served in many species for digging.
The early Dicynodontier ( Eodicynodon, Diictodon ) were with little more than 30 cm in length is still relatively small and probably lived in underground passages, which offered them protection from predators such as the gorgonopsians. Few genres of Dicynodontier survived the great extinctions at the end of the Permian, which obliterated about 90 % of all species living on earth as distinguished as the trilobites in the sea and the Pareiasaurier ashore.
In the Triassic period some groups of Dicynodontier underwent another Radiation and developed species with significantly larger bodies. Of these later Dicynodontiern presumably living in large herds Lystrosaurus was still one of the smallest. Very much larger, however, were Kannemeyeria with a length of about 3 meters and Placerias, a hippopotamus -like Dicynodontier with about 3.5 meters in length and weighing about a ton. Lystrosaurus was in the early Triassic, the dominant genus of herbivorous vertebrates.
In contrast to earlier representatives of this group, they had to be wary before the Triassic archosaurs widespread as Proterosuchus or Postosuchus. Occasionally could be dangerous to them even at that time still relatively small dinosaur Coelophysis and cynodonts such as Cynognathus, because it is believed that these hunted in packs. However, they have been as herd animals not easy prey. Shortly after the beginning of the Jurassic they still died out gradually, won at a time when herbivorous cynodonts and especially herbivorous dinosaurs in importance.
System
- Dicynodontia Eodicynodon
- Endothiodon
- Kingoria
- Diictodontoidea Robertia
- Emydops
- Diictodon
- Cistecephalus
- Kawingasaurus
- Myosaurus
- Pristerodon
- Oudenodon
- Aulacocephalodon
- Dinanomodon
- Dicynodon
- Lystrosaurus
- Kannemeyeriidae Shansiodon
- Tetragonias
- VINCERA
- Kannemeyeria
- Stahleckeria
- Elephantosaurus
- Zambiasaurus
- Placerias
- Ischigualastia