Template:Short description Template:Distinguish Template:About Template:Automatic taxobox
Elephas is a genus of elephants and one of two surviving genera in the family Elephantidae, comprising one extant species, the Asian elephant (E. maximus).<ref name = MSW3>Template:MSW3 Proboscidea</ref> Several extinct species have been identified as belonging to the genus, extending back to the Pliocene or possibly the late Miocene.
DescriptionEdit
Species of Elephas have distinct bossing of the parieto-occipital region of the skull. The premaxillae bones containing the tusks are tapered.<ref>Template:Cite journal</ref>
Evolutionary historyEdit
Relationships of living and extinct elephantids based on DNA, after Palkopoulou et al. 2018.<ref name=":02">Template:Cite journal</ref>Template:CladeAsian elephants share a closer common ancestry with mammoths (genus Mammuthus) than they do with African elephants (Loxodonta).<ref name="Fleischer2001">Template:Cite journal</ref> The oldest species attributed to the genus Elephas is E. nawataensis from the Late Miocene-Early Pliocene of Kenya, though the validity of this species and its relationship to Elephas has been doubted.<ref name=":3">Template:Cite journal</ref> The oldest species widely attributed to the genus, Elephas ekorensis is known from the early-mid Pliocene (5–4.2 million years ago) of East Africa,<ref>Template:Cite journal</ref> though the attribution of this species to Elephas has been questioned, due to a lack of shared morphological features with later Elephas species.<ref name=":1">Template:Cite journal</ref> The oldest record of the genus outside of Africa is Elephas planifrons which is known from the Late Pliocene of the Indian subcontinent, around 3.6 million years ago.<ref>Template:Cite journal</ref> However, the placement of Elephas planifrons within the genus has also been questioned.<ref>H. Zhang Elephas recki: the wastebasket? 66th Symposium of Vertebrate Palaeontology and Comparative Anatomy, Manchester. (2018)</ref> The earliest fossils of the ancestor of the modern Asian elephant, Elephas hysudricus date to the beginning of the Pleistocene, around 2.6 million years ago, with remains found on the Indian subcontinent.<ref name=":0">Template:Cite journal</ref> Modern Asian elephants had evolved from E. hysrudicus by the Late Pleistocene.<ref>Template:Cite journal</ref>
TaxonomyEdit
The scientific name Elephas was proposed by Carl Linnaeus in 1758 who described the genus and an elephant from Ceylon.<ref>Template:Cite book</ref> The genus is assigned to the proboscidean family Elephantidae and is made up of one living and seven extinct species:<ref name=Maglio1973>Maglio, V.J. (1973). "Origin and evolution of the Elephantidae". Transactions of the American Philosophical Society, Philadelphia Volume 63. American Philosophical Society, Philadelphia, pp. 149</ref>
- Elephas maximus – Asian elephant<ref name = MSW3/>
- Elephas maximus indicus – Indian elephant
- Elephas maximus maximus – Sri Lankan elephant
- Elephas maximus sumatranus – Sumatran elephant
- Elephas maximus borneensis – Borneo elephant, proposed but not yet recognized as valid<ref name=Fernando03>Fernando, P., Vidya, T.N.C., Payne, J., Stuewe, M., Davison, G., et al. (2003). DNA Analysis Indicates That Asian Elephants Are Native to Borneo and Are Therefore a High Priority for Conservation. PLoS Biol 1 (#1): e6</ref>
The following Asian elephants were proposed as extinct subspecies, but are now considered synonymous with the Indian elephant:<ref name = MSW3/>
- Elephas maximus sondaicus – Javan elephant †
- Elephas maximus rubridens – Chinese elephant †
- Elephas maximus asurus – Syrian elephant †
The following Elephas species are extinct:
- Elephas beyeri – dwarf elephant species described from fossil remains found in 1911 in Luzon, the Philippines by von Königswald<ref>Von Königswald, G.H.R. (1956). Fossil mammals from the Philippines. National Research Council of the Philippines, Manila</ref>
- Elephas ekorensis – described from the Kubi Algi Formation, Turkana, Kenya,<ref name=Maglio1973/> dating to the Early Pliocene, one of the oldest species of the genus.<ref name="Sanders-2012">Template:Cite journal</ref>
- Elephas hysudricus – described from fossil remains found in the Siwalik Hills of the northern Indian subcontinent by Falconer and Cautley, 1845,<ref>Falconer, H. & Cautley, P. T. (1846). Fauna Antiqua Sivalensis, Being the Fossil Zoology of the Sewalik Hills. Smith, Elder & Company, London, pp. 64.</ref> thought to be the ancestor of the living Asian elephant.<ref>Template:Cite journal</ref>
- Elephas hysudrindicus – a fossil elephant of the Pleistocene of Java and different from Elephas maximus sondaicus<ref>Hooijer, D. A. (1955). Fossil Proboscidea from the Malay Archipelago and the Punjab. Zoologische Verhandelingen, 28 (#1): 1–146.</ref>
- Elephas planifrons - one of the oldest species, known from the Late Pliocene-Early Pleistocene of the Indian subcontinent.<ref name="ReferenceA">Template:Cite journal</ref>
- Elephas platycephalus a species sometimes recognised from the Pleistocene of India
- Elephas kiangnanensis a species sometimes recognised from the Early-Middle Pleistocene of China.<ref>Template:Cite journal</ref><ref>Haowen Tong & M. Patou-Mathis. (2003). Mammoth and other proboscideans in China during the Late Pleistocene. Deinsea, 9(1), 421–428.</ref>
- Elephas nawataensis a species of elephant known from the Late Miocene-Early Pliocene of Kenya, though other authors argue that this species is actually a synonym of Primelephas korotorensis.<ref name=":3" />
- Elephas atavus? known from the Early Pleistocene of Africa, traditionally considered part of Elephas/Palaeoloxodon recki
While formerly assigned to this genus, Elephas recki, Elephas namadicus, the straight-tusked elephant E. antiquus and the dwarf elephants E. falconeri and E. cypriotes are now placed in the separate genus Palaeoloxodon, which is more closely related to African elephants.<ref name=":5">Template:Cite journal</ref> However, some material historically assigned to Elephas recki , such as Elephas recki atavus, may be closely related to true Elephas, rather than to Palaeoloxodon<ref name=":2">Template:Cite book</ref> "Elephas" celebensis is now placed in Stegoloxodon.<ref name=":03">Template:Cite journal</ref>