The Proboscidea are 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. From the mid-Miocene onwards, most proboscideans were very large. The largest land mammal of all time may have been a proboscidean; Palaeoloxodon namadicus was up to 5.2 m (17.1 ft) at the shoulder and may have weighed up to 22 t, almost double the weight of some sauropods like Diplodocus carnegii. The largest extant proboscidean is the African bush elephant, with a record of size of 4 m (13.1 ft) at the shoulder and 10.4 t. In addition to their enormous size, later proboscideans are distinguished by tusks and long, muscular trunks, which were less developed or absent in early proboscideans.
Deinotherium was a large prehistoric relative of modern-day elephants that appeared in the Middle Miocene and survived until the Early Pleistocene. During that time, it changed very little. In life, it probably resembled modern elephants, except it had downward-curving tusks attached to the lower jaw.
Mammutidae is an extinct family of proboscideans that appeared during the Oligocene epoch and survived until the start of the Holocene. The family was first described in 1922, classifying fossil specimens of the type genus Mammut (mastodons), and has since been placed in various arrangements of the order. The name "mastodon" derives from Greek, μαστός "nipple" and ὀδούς "tooth", as with the genus, referring to a characteristic that distinguishes them from allied families. The genus Zygolophodon has also been assigned to this family. Mammutids ranged very widely, with fossils found in North America, Africa, and throughout Eurasia.
Gomphotheres are any members of the diverse, extinct taxonomic family Gomphotheriidae. Gomphotheres were elephant-like proboscideans, but not belonging to the family Elephantidae. They were widespread in across Afro-Eurasia and North America during the Miocene and Pliocene epochs and dispersed into South America during the Pleistocene following the Great American Interchange. Gomphotheriidae in its broadest sense is probably paraphyletic with respect to Elephantidae, which contains modern elephants. While most famous forms such as Gomphotherium had long lower jaws with tusks, which is the ancestral condition for the group, after these forms became extinct, the surviving gomphotheres had short jaws with either vestigal or no lower tusks (brevirostrine), looking very similar to modern elephants, an example of parallel evolution. During the Pleistocene epoch, most gomphotheres became extinct, with the last two genera, Cuvieronius persisting in southern North America and Notiomastodon having a wide range over most of South America until the end of the Pleistocene and human arrival in the Americas around 11,000 years ago.
Deinotheriidae is a family of prehistoric elephant-like proboscideans that lived during the Cenozoic era, first appearing in Africa, then spreading across southern Asia (Indo-Pakistan) and Europe. During that time, they changed very little, apart from growing much larger in size; by the late Miocene, they had become the largest land animals of their time. Their most distinctive features were the downward-curving tusks on the lower jaw.
Prodeinotherium is an extinct representative of the family Deinotheriidae that lived in Africa, Europe, and Asia in the early and middle Miocene. Prodeinotherium, meaning "before terrible beast", was first named in 1930, but soon after, the only species in it, P. hungaricum, was reassigned to Deinotherium. During the 1970s, however, the two genera were once again separated, with Prodeinotherium diagnosed to include Deinotherium bavaricum, Deinotherium hobleyi, and Deinotherium pentapotamiae, which were separated based on geographic location. The three species are from Europe, Africa, and Asia, respectively. However, because of usage of few characters to separate them, only one species, P. bavaricum, or many more species, including P. cuvieri, P. orlovii, and P. sinense may be possible.
Gomphotherium is an extinct genus of proboscids from the Neogene and early Pleistocene of Eurasia, Africa, North America and possibly also Asia.
Anancus is an extinct genus of elephantoid proboscidean native to Afro-Eurasia, that lived from the Tortonian stage of the late Miocene until the genus' extinction during the early Pleistocene, roughly from 8.5–2 million years ago.
Cuvieronius is an extinct New World genus of gomphothere, named after the French naturalist Georges Cuvier. Alive, specimens typically stood about 2.3 m tall at the shoulder, weighed about 3.5 t and would have superficially resembled a modern elephant with spiral-shaped tusks.
Stegomastodon is an extinct genus of gomphotheres, a family of proboscideans. It ranged throughout North America from the early Blancan ~4 Ma, to the early Irvingtonian. The South American species have been synonymized with Notiomastodon platensis.
Sinomastodon is an extinct gomphothere genus, from the Late Miocene to the Early Pleistocene deposits of Asia. It is not to be confused with the genus Mammut from a different proboscidean family, whose members are commonly called "mastodons".
Tetralophodon is an extinct proboscidean genus belonging to the superfamily Elephantoidea.
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. Like other gomphotheres it had a superficially elephant-like appearance with a trunk and tusks.
Notiomastodon is an extinct proboscidean genus of gomphotheres endemic to South America from the Pleistocene to the Holocene. It was among the last known gomphotheres and one of two South American gomphotheres alongside Cuvieronius, and was the predominant gomphothere on the continent ranging widely over most of South America excluding the high Andes. The species has a long and convoluted taxonomic history due to its morphological variability and confusion with related gomphothere taxa, which was only resolved during the 2010s.
Surameryx is an extinct genus of herbivorous even-toed ungulates originally described as belonging to the extinct family Palaeomerycidae. A single species, S. acrensis, was described from the Late Miocene of the Madre de Dios Formation, South America. It was originally interpreted as one of the few northern mammals that entered South America before the Pliocene. However, both its identification as a member of the family Palaeomerycidae and claims about its Miocene age were subsequently challenged.
Sinomammut is a proboscidean found in the Miocene of China. It was known from a single, fragmentary, mandible found in the 1990s. However, most of the specimen has been lost, leaving only the right ramus and an in-situ photograph of the mandible. The mandible was originally thought a gompothere closely related to Sinomastodon, but an analysis revealed it to actually be a mammutid that was a sister group to the well-known mastodon. It can be distinguished from the mastodon by its lack of lower tusks.
Amebelodontidae is an extinct family of large herbivorous mammals that were closely related to elephants. They were formerly assigned to Gomphotheriidae, but recent authors consider them a distinct family.
Eurybelodon is an extinct genus of proboscidean in the family Amebelodontidae.
