Amphilestidae

Life image of Gobiconodon

• Eurasia, North America, Africa

The Amphilestidae are a group of extinct mammals ( Mammalia), who lived in the Middle and Upper Jurassic.

Features

The Amphilestidae as some other Mesozoic mammals (which are collectively Eutriconodonta ), characterized by three bumps arranged in a row on each molar ( molar ). In contrast to the Triconodontidae the middle hump is with them, however, significantly larger than the other two and the groove-like connection between the back teeth missing. Amphilestes, the eponymous genus, should have possessed four incisors, one canine, four premolars and five molars in the mandible per half of the jaw. In addition to teeth and jaw parts does not finds these animals are known, but the findings suggest a carnivorous lifestyle.

System

The few fossils difficult to exactly define the Amphilestidae and their systematic classification. A dreihöckriger construction of the molars is also of numerous other Mesozoic mammals known whether these animals are a natural group ( Eutriconodonta ) or simply convergent developments, is controversial. Their position in the scheme of mammals is unclear, it is likely, however, have been a relatively early, specialized side branch. With today's mammals are not closely related.

Related Undoubtedly close together, only the genera Amphilestes and Phascolotherium who both lived in the Middle Jurassic and were discovered by Richard Owen in England. Other genera that are filed with reservation in this group, Aploconodon, Comodon and Triconolestes are (all from the Upper Jurassic of North America ), Liaotherium (from the Middle Jurassic of China ) and Tendagurodon, which was discovered in Tendaguru (Tanzania ) and could be an indication that that these animals were also common in the former southern continent Gondwana.