Astrapotheria
Astrapotherium magnum
- South America
- Antarctic
The Astrapotheria are a completely extinct order of herbivorous ( herbivorous ) mammals from the superiority of the South American ungulates ( Meridiungulata ). They lived before 58.7 to 7.25 million years, ie from the upper Paleocene to the Miocene, on the South American continent. They probably represent the sister taxon of Xenungulata dar.
Description
The more developed Astrapotheria ( Astrapotheriidae ) had often large-sized and elongated body comparatively slender limbs. The neck was extended and ended with a rather large and heavily built head. From the skull structure, especially from the recessed nasal bones suggests the presence of a short, strong proboscis. Superficially Astrapotheria had a resemblance to recent tapirs, without being more closely related to these. The canine teeth ( dentes canini ) were lengthened tusk -like, to them, a wide gap closed ( the so-called diastema ) in front of the molar teeth ( molars ) to. The function of the canine teeth is unknown. The lower jaw bone ( mandible ) sticking out far beyond the upper jaw (maxilla ). It seems that the Astrapotheriidae had developed a habit by convergent evolution between the today's rhinos and elephants and a similar way of life had. However, also belonging to the Südhuftieren Pyrotheria elephants were even more similar.
Untertaxa
The early Eoastrastylopidae were the smallest and most primitive among the Astrapotheria. Of them, only one type is known. They lived from the Paleocene to the early Eocene, about 55 million years ago. The Trigonostylopidae have long been regarded as a separate family. You are guaranteed to 45 million years ago. The later, more specialized and large representative of Astrapotheriidae characterize the Astrapotheria; they died out around 10 million years ago at the end of the Miocene.
Families and genera
- Eoastrastylopidae Eoastropostylops
- Shecenia
- Tetragonostylops
- Trigonostylops
- Albertogaudrya
- Astraponotus
- Astrapotherium
- Astrapothericulus
- Isolophodon
- Monoeidodon
- Parastrapotherium
- Scaglia
- Synastrapotherium
- Uruguaytherium
- Xenastrapotherium
Representative
The well-known mainly from skeletal remains Trigonostylops Paleocene is still regarded as a primitive form. He was about 1.5 meters in length significantly smaller than the Astrapotheriidae Xenastrapotherium, Uruguaytherium and 2.5 to 3 meters wide Astrapotherium.
Swell
- Malcolm C. McKenna, Susan K. Bell: Classification of mammals above the species level. Revised edition. Columbia University Press, New York, NY 2000, ISBN 0-231-11013-8.