Elephantiformes Temporal range: | |
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Skull of Phiomia | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Proboscidea |
Suborder: | Elephantiformes Tassy, 1988 |
Subgroups [1] | |
Elephantiformes is a suborder within the order Proboscidea. [1] Members of this group are primitively characterised by the possession of upper tusks, an elongated mandibular symphysis (the frontmost part of the lower jaw) and lower tusks, and the retraction of the facial region of the skull indicative of the development of a trunk. [2] The earliest known member of the group, Dagbatitherium is known from the Eocene (Lutetian) of Togo, which is only known from isolated teeth, while other primitive elephantiforms like Phiomia and Palaeomastodon are known from the Early Oligocene onwards. [3] Phiomia and Palaeomastodon are often collectively referred to as "palaeomastodonts" and assigned to the family Palaeomastodontidae. [4] Most diversity of the group is placed in the subclade Elephantimorpha, which includes mastodons (family Mammutidae), as well as modern elephants and gomphotheres (Elephantida). [3] It is disputed as to whether Phiomia is closely related to both Mammutidae and Elephantida with Palaeomastodon being more basal, or if Palaeomastodon is closely related to Mammutidae and Phiomia more closely related to Elephantida. [4]
Phylogeny of Proboscidea including Elephantiformes, following Hautier et al. 2021 [3]
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.
A mastodon is a member of the genus Mammut, which was endemic to North America and lived from the late Miocene to the early Holocene. Mastodons belong to the order Proboscidea, the same order as elephants and mammoths. Mammut is the type genus of the extinct family Mammutidae, which diverged from the ancestors of modern elephants at least 27–25 million years ago, during the Oligocene.
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.
Elephas is one of two surviving genera in the family of elephants, Elephantidae, with one surviving species, the Asian elephant, Elephas maximus. Several extinct species have been identified as belonging to the genus, extending back to the Pliocene or possibly the late Miocene.
Moeritherium is an extinct genus of basal proboscideans from the Eocene of North and West Africa. It was related to elephants and, more distantly, to sea cows and hyraxes.
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.
Palaeoloxodon recki, often known by the synonym Elephas recki, is an extinct species of elephant native to Africa and West Asia from the Pliocene or Early Pleistocene to the Middle Pleistocene. During most of its existence, the species represented the dominant elephant species in East Africa. The species is divided into five roughly chronologically successive subspecies. While the type and latest subspecies P. recki recki as well as the preceding P. recki ileretensis are widely accepted to be closely related and ancestral to Eurasian Palaeoloxodon, the relationships of the other, chronologically earlier subspecies to P. recki recki, P. recki ileretensis and Palaeoloxodon are uncertain, with it being suggested they are unrelated and should be elevated to separate species.
Phiomia is an extinct genus of basal elephantiform proboscidean that lived in what is now Northern Africa during the Late Eocene to Early Oligocene some 37–30 million years ago. "Phiomia serridens" means "saw-toothed animal of Faiyum".
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.
Numidotherium is an extinct genus of early proboscideans, discovered in 1984, that lived during the middle Eocene of North Africa some 46 million years ago. It was about 90–100 cm (35–39 in) tall at the shoulder and weighed about 250–300 kg (550–660 lb).
Palaeomastodon is an extinct genus within the elephant order Proboscidea. Its fossils have been extracted from Oligocene strata conventionally dated to 33.9-23.03 million years old. Usually considered an ancestor or near-ancestor of elephants or mastodons as a member of Elephantiformes it lived in marshes and fluvial-deltaic environments of what is now Egypt, Ethiopia, Libya, and Saudi Arabia.
Zygolophodon is an extinct genus of mammutid proboscidean that lived during the Miocene in Africa, Eurasia, and North America.
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.
Elephantimorpha is a clade of proboscideans that contains the Mammutidae (mastodons), as well as Elephantida. All members of this group have the horizontal tooth replacement typical of modern elephants, unlike more primitive members of the Elephantiformes. Like modern elephants, the ancestor of Elephantimorpha was likely capable of communicating via infrasonic calls. While early elephantimorphs generally had lower jaws with an elongated mandibular symphysis at the front of the jaw with well developed lower tusks/incisors, from the Late Miocene onwards, many groups convergently developed brevirostrine (shortened) lower jaws with vestigial or no lower tusks, probably corresponding with the elongation and increasingly dexterity of the trunk allowing it to be used as the primary feeding organ.
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.
Eozygodon is an extinct genus of proboscidean in the family Mammutidae that is based on a single species, E. morotoensis, named in 1983. It is known from the Early Miocene of Africa and well as possibly the Middle Miocene of China. It is considered a primitive member of the family, retaining a long lower jaw (longirostrine) with lower tusks. The upper tusks are small, and are parallel to each other. The skull of the young adult AM 02 from Auchas, Namibia, was around the size of that of a 10 year old American mastodon, around 60 centimetres (2.0 ft) in maximum length. Dental mesowear from East African specimens suggests a browsing diet. Some authors suggest that Eozygodon could be less closely related to other members of Mammutidae than other mammutids are to Elephantida, making Mammutidae as typically defined paraphyletic.
Arcanotherium is an extinct genus of early proboscidean belonging to the family Numidotheriidae that lived in North Africa during the late Eocene/early Oligocene interval.
Dagbatitherium is an extinct genus of proboscideans. So far a single molar from the phosphate basins of Togo in West Africa has been found. The fossil dates to the Middle Eocene, around 47 million years ago. A striking feature of the tooth are the three pairs of cusps oriented transversely to the longitudinal axis of the tooth. This feature is found in more derived proboscideans, which are grouped in the Elephantiformes. For its age, Dagbatitherium is the earliest member of Elephantiformes to date. Furthermore, it is characterized by a low tooth crown and a humped occlusal pattern. The genus was described in 2021.
"Mammut" borsoni is an extinct species of mammutid proboscidean known from the Late Miocene to Early Pleistocene of Eurasia, spanning from western Europe to China. It is the last known mammutid in Eurasia, and amongst the largest of all proboscideans and largest known land mammals.