Temporal range: Miocene–Pliocene
|Fossil skull and tusks of T. longirostris, from Ballestar, Spain at the Museu Geològic del Seminari de Barcelona, Barcelona|
The genus Tetralophodon (meaning "four-ridged tooth") was named in the mid-19th century with the discovery of the specialized teeth.
Like typical gomphotheres, mastodons with four tusks, Tetralophodon had four tusks and a trunk. In fact, also this animal had two further tusks protruding from the jaw. The overall appearance recalled Gomphotherium, the best known genus of the family Gomphotheriidae.
Their body is believed to be about 3 m (10 ft) tall and one ton in weight, about the size of the present Asian elephant, with the long trunk and incisors ranging up to 2 m (6.6 ft) long. These incisors are believed to be utilized as a defense mechanism
The large, four-cusped cheek teeth of these animals are approximately 60 mm (2.4 in) by 80 mm (3.1 in), about 6 times the size of a normal human tooth. These low-crowned, bunodont teeth are designed for crushing and grinding, compared with other mammals during this era that had sharp teeth used for cutting. The teeth of the tetralophodon indicate a diet of large fruits and vegetables. This diet is aided by the large size and long trunks of the elephantiods that enable these mammals to reach tall, fruit-bearing trees.
Some features, mainly concerning the teeth, would seem to place Tetralophodon close to the origin of today's elephants. The molars, in particular, are more advanced and specialized than those of the other gomphotheres.
These animals were very widespread and successful proboscideans. Their fossils have been found in the late Miocene and early Pliocene epochs of Europe, Asia, and Africa. Most fossil records of tetralophodon are of four-ridged teeth. The North American species, T. campester and T. fricki, have been moved to the genus Pediolophodon in 2007.
The majority of the gomphotheres went extinct at the end of the Pleistocene era, during what has been named the PT extinction. While the reason for this extinction is still debated, what is known is that these massive elephantoids under the genus Tetralophodon did not survive.
- Ugan, A.; Byers, D. (2007). "Geographic and temporal trends in proboscidean and human radiocarbon histories during the late Pleistocene". Quaternary Science Reviews 26 (25–28): 3058. Bibcode:2007QSRv...26.3058U. doi:10.1016/j.quascirev.2007.06.024.
- Lambert, W. D. (2007). "New tetralophodont gomphothere material from Nebraska and its implications for the status of North AmericanTetralophodon". Journal of Vertebrate Paleontology 27 (3): 676–673. doi:10.1671/0272-4634(2007)27[676:NTGMFN]2.0.CO;2.
- "The Paleobiology Database:Tetralophodon". Retrieved 2012-03-07.