Amebelodon Temporal range: | |
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Mandible assigned to A. fricki | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Proboscidea |
Family: | † Amebelodontidae |
Genus: | † Amebelodon Barbour, 1927 |
Species | |
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Amebelodon is a genus of extinct proboscidean belonging to Amebelodontidae (the so-called shovel-tuskers). The most striking attribute of this animal is its lower tusks, which are narrow, elongated, and distinctly flattened with the degree of flattening varying among the different species. One valid species is known for this genus, which was endemic to North America. Other species once assigned to Amebelodon are now assigned to the genus Konobelodon , which was once a subgenus. [1]
Amebelodon first appeared in the Great Plains and Gulf Coast regions of North America during the late Miocene, roughly 9 million years ago, and apparently became extinct on this continent sometime around 6 million years ago. The youngest record of Amebelodon is from a 5-million-year-old site in North America. [2] [3] [4] The species Amebelodon floridanus was relatively small, a little smaller than living elephants, and was common in fossil sites from 9 to 8 million years ago. Other larger but somewhat younger common North American species include Amebelodon fricki. [4] One lineage of species once assigned to Amebelodon, including Amebelodon britti and North African Amebelodon cyrenaicus, is now placed in a separate genus called Konobelodon, formerly considered to be a subgenus. [1]
Like other typical gomphotheres, Amebelodon possessed two sets of tusks, one upper set, (much like those found on modern elephants), and one lower set that extended from the very front of the lower jaws. However, as mentioned above, the lower tusks of the Amebelodon were distinctive in that they were relatively long, slender, and flattened. Because of the resemblance of these lower tusks to shovels, Amebelodon is commonly referred to as a "shovel-tusked" gomphothere (another shovel-tusked gomphothere that may or may not be closely related to Amebelodon is Platybelodon ). There has long been an assumption that these lower tusks were actually used as shovels by the animal during feeding, presumably to dig up water plants. However, an analysis of wear patterns has shown that these lower tusks were most likely used in a variety of ways in addition to shoveling, including scraping bark from trees. [4] [5] Overall, the evidence indicates that this animal was a versatile browser (an animal that eats broad-leaved plants rather than grass), feeding in both wet and dry settings in a variety of ways. For reasons that are not clearly explained in the literature, Amebelodon is usually portrayed with a short, flap-like trunk (this is true of the associated picture). However, considerable evidence indicates that Amebelodon actually had a long, flexible trunk very much like that found in modern elephants, and that it probably was important for feeding, drinking, etc. [4] [5]
Amebelodon was once thought to be widespread, but a study of Konobelodon in 2012 shortened the genus' range span, with the specimens found in China moved to the genus Protanancus . [6]
Proboscidea is a taxonomic order of afrotherian mammals containing one living family (Elephantidae) and several extinct families. First described by J. Illiger in 1811, it encompasses the elephants and their close relatives. Three species of elephant are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant.
Mammutidae is an extinct family of proboscideans belonging to Elephantimorpha. It is best known for the mastodons, which inhabited North America from the Late Miocene until their extinction at beginning of the Holocene, around 11,000 years ago. The earliest fossils of the group are known from the Late Oligocene of Africa, around 24 million years ago, and fossils of the group have also been found across Eurasia. The name "mastodon" derives from Greek, μαστός "nipple" and ὀδούς "tooth", referring to their characteristic teeth.
Platybelodon is an extinct genus of large herbivorous proboscidean mammals related to modern-day elephants, placed in the "shovel tusker" family Amebelodontidae. Species lived during the middle Miocene Epoch in Africa, Asia and the Caucasus.
Gomphotheres are an extinct group of proboscideans related to modern elephants. First appearing in Africa during the Oligocene, they dispersed into Eurasia and North America during the Miocene and arrived in South America during the Pleistocene as part of the Great American Interchange. Gomphotheres are a paraphyletic group ancestral to Elephantidae, which contains modern elephants, as well as Stegodontidae.
Gomphotherium is an extinct genus of gomphothere proboscidean from the Neogene of Eurasia, Africa and North America. It is the most diverse genus of gompothere, with over a dozen valid species. The genus is probably paraphyletic.
Anancus is an extinct genus of "tetralophodont gomphothere" native to Afro-Eurasia, that lived from the Tortonian stage of the late Miocene until its extinction during the Early Pleistocene, roughly from 8.5–2 million years ago.
Tetralophodon is an extinct genus of "tetralophodont gomphothere" belonging to the superfamily Elephantoidea, known from the Miocene of Afro-Eurasia.
Paratetralophodon is an extinct genus of proboscidean from late Neogene deposits in India and China. Although traditionally classified in the family Gomphotheriidae, recent studies find it to be more closely related to modern elephants.
Archaeobelodon is an extinct genus of proboscidean of the family Amebelodontidae that lived in Europe and North Africa (Egypt) during the Miocene from 16.9 to 16.0 Ma, living for approximately 0.9 million years.
Gnathabelodon is an extinct genus of gomphothere endemic to North America that includes species that lived during the Middle to Late Miocene.
Eubelodon is an extinct genus of gomphothere which lived in North America during the Miocene Epoch. It contains a single species: Eubelodon morrilli.
Serbelodon is an extinct genus of proboscidean. It had tusks and a trunk. It lived in North America during the Miocene Epoch, and it was closely related to Amebelodon. They had a diet that consisted of C3 plants which include fruits, tree cortex, herbs, and leaves.
Notiomastodon is an extinct genus of gomphothere proboscidean, endemic to South America from the Pleistocene to the beginning of the Holocene. Notiomastodon specimens reached a size similar to that of the modern Asian elephant, with a body mass of 3-4 tonnes. Like other brevirostrine gomphotheres such as Cuvieronius and Stegomastodon, Notiomastodon had a shortened lower jaw and lacked lower tusks, unlike more primitive gomphotheres like Gomphotherium.
Choerolophodon is an extinct genus of proboscidean that lived during the Miocene of Eurasia and Africa. Fossils of Choerolophodon have been found in Africa, Southeast Europe, Turkey, Iraq, Iran, the Indian subcontinent, and China.
Konobelodon is an extinct genus of amebelodont proboscidean from the Miocene of Africa, Eurasia and North America.
Amebelodontidae is an extinct family of large herbivorous proboscidean mammals related to elephants. They were formerly assigned to Gomphotheriidae, but recent authors consider them a distinct family. They are distinguished from other proboscideans by having flattened lower tusks and very elongate mandibular symphysis. The lower tusks could grow to considerable size, with those of Konobelodon reaching 1.61 metres (5.3 ft) in length. Their molar teeth are typically trilophodont, and possessed posttrite conules. In the past, amebelodonts' shovel-like mandibular tusks led to them being portrayed scooping up water plants, however, dental microwear suggests that they were browsers and mixed feeders. The lower tusks have been proposed to have had a variety of functions depending on the species, including stripping bark, cutting through vegetation, as well as possibly digging. They first appeared in Africa during the Early Miocene, and subsequently dispersed into Eurasia and then North America. They became extinct by the beginning of the Pliocene. While some phylogenetic studies have recovered Amebelodontidae as a monophyletic group that forms the sister group to Gomphotheriidae proper, some authors have argued that Amebelodontidae may be polyphyletic, with it being suggested that the shovel-tusked condition arose several times independently within Gomphotheriidae, thus rendering the family invalid.
Torynobelodon was a genus of large herbivorous mammal related to the elephant. It lived during the late Miocene Epoch in Asia and North America.
Eurybelodon is an extinct genus of proboscidean in the family Amebelodontidae. It lived in the Clarendonian age of the Miocene.
Protanancus is an extinct genus of amebelodontid proboscidean from Kenya, Pakistan and Thailand. The genus consists solely of type species P. macinnesi. The generic name is derived from the unrelated Anancus, and the Greek prōtos "first".
Stenobelodon is an extinct genus of amebelodont proboscidean from the Miocene of North America. The only known species was formerly considered to belong to the genus Amebelodon but was distinguished in 2023 based on the short and only partially flattened lower tusks and the closer resemblance of its cheek teeth to those of Gomphotherium than to its purported close relatives. Fossils are known from Florida and Kansas.