Elephantidae

African forest elephant Loxodonta africana cyclotis, from here.


Belongs within: Elephantida.
Contains: Elephas.

The Elephantidae, elephants, first appeared in the late Pliocene and are distinguished from earlier proboscideans by their distinctive 'conveyor-belt' mode of tooth development. The greatly enlarged adult molars develop sequentially rather than all at once, so that only one or two molars are functional at any one time. As each functioning molar becomes worn down through use, its developing successor moves forward to take its place. In the most basal elephantids, the lower premolars were also present, and the molars retained distinct crowns; in the Elephantinae, the premolars became non-functional and the molar crowns became pressed together into a series of laminae. Except for Stegotetrabelodon and Primelephas, elephantids also lost the lower tusks of earlier proboscideans (Coppens et al. 1978).

Living elephants belong to two genera, Elephas and Loxodonta. The African elephant Loxodonta africana is distinguished from Elephas by its concave back and trunk with two terminal 'fingers'.

Synapomorphies (from Tassy & Shoshani 1988): basicranium elevated; loss of enamel band on upper tusks; molars with five or more lophids, becoming laminae.

<==Elephantidae [Stegotetrabelodontinae]
    |--Stegotetrabelodon Petrocchi 1941 TS88, CM78
    |    |--*S. syrticus Petrocchi 1941 [incl. S. lybicus Petrocchi 1941, S. sahabianus Petrocchi 1943] CM78
    |    `--S. orbus Maglio 1970 CM78
    `--+--Stegodibelodon Coppens 1972 TS88, CM78
       |    `--*S. schneideri Coppens 1972 CM78
       `--Elephantinae CM78
            |--Primelephas Maglio 1970 CM78
            |    |--*P. gomphotheroides Maglio 1970 CM78
            |    `--P. korotorensis (Coppens 1965) [=Stegodon korotorensis] CM78
            `--+--+--Elephas FS15
               |  `--Loxodonta Cuvier 1825 FS15, CM78
               |       |--*L. africana (Blumenbach 1797) (see below for synonymy) CM78
               |       |    |--L. a. africana B84
               |       |    `--L. a. cyclotis B84
               |       |--L. adaurora Maglio 1970 CM78
               |       `--L. atlantica (Pomel 1879) [=Elephas atlanticus; incl. E. pomeli Arambourg 1952] CM78
               |            |--L. a. atlantica CM78
               |            `--L. a. zulu (Scott 1907) [=Elephas (Loxodon) zulu] CM78
               `--Mammuthus Burnett 1830 FS15, AC98 (see below for synonymy)
                    |  i. s.: ‘Archidiskodon’ gromovi D07
                    |         M. jeffersoni D07
                    |         M. lamarmorae D07
                    |--M. subplanifrons (Osborn 1928) (see below for synonymy) CM78
                    `--+--M. africanavus (Arambourg 1952) [=Elephas africanavus, Loxodonta africanava] CM78
                       `--+--M. meridionalis (Nesti 1825) (see below for synonymy) CM78
                          |--+--*M. primigenius (Blumenbach 1799) CM78 (see below for synonymy)
                          |  `--M. armeniacus [=Parelephas armeniacus; incl. M. trogontherii] CM78
                          `--+--M. columbi CM78 [=Elephas primigenius columbi FP64, C77, Parelephas columbi CM78]
                             |--M. exilis Stock & Furlong 1928 FS15, AC98
                             `--M. imperator CM78 [=Archidiskodon imperator CM78, Elephas imperator FP64]

*Loxodonta africana (Blumenbach 1797) [=Elephas africanus; incl. L. atlantica angammensis Coppens 1965, L. prima Dart 1929] CM78

Mammuthus Burnett 1830 TS88, AC98 [incl. Archidiskodon Pohlig 1888 AC98, Cheirolites von Meyer 1848 AC98, Dicyclotherium GĂ©offroy-Saint-Hilaire 1837 AC98, Mammonteus Camper in Osborn 1924 AC98, Metarchidiskodon Osborn 1934 AC98, Paraelephas Osborn 1924 AC98]

Mammuthus meridionalis (Nesti 1825) [=Elephas meridionalis, Archidiskodon meridionalis; incl. E. moghrebiensis Arambourg 1970] CM78

*Mammuthus primigenius (Blumenbach 1799) CM78 [=Elephas primigenius FP64, Mammonteus primigenius CM78]

Mammuthus subplanifrons (Osborn 1928) [=Archidiskodon subplanifrons; incl. A. andrewsi Dart 1929, A. planifrons nyanzae MacInnes 1942, Mammuthus (Archidiskodon) scotti Meiring 1955] CM78

*Type species of generic name indicated

REFERENCES

[AC98] Alcover, J. A., X. Campillo, M. Macias & A. Sans. 1998. Mammal species of the world: additional data on insular mammals. American Museum Novitates 3248: 1–29.

[B84] Barnes, R. F. W. 1984. Elephants. In: Macdonald, D. (ed.) All the World’s Animals: Hoofed Mammals pp. 12–21. Torstar Books: New York.

[C76] Cope, E. D. 1877. Report upon the extinct Vertebrata obtained in New Mexico by parties of the expedition of 1874. Geographical Surveys West of the One Hundredth Meridian 4 (2): i–iv, 1–370.

[CM78] Coppens, Y., V. J. Maglio, C. T. Madden & M. Beden. 1978. Proboscidea. In: Maglio, V. J., & H. B. S. Cooke (eds) Evolution of African Mammals pp. 336–367. Harvard University Press: Cambridge (Massachusetts).

[D07] Dixon, D. 2007. The Complete Illustrated Encyclopedia of Dinosaurs & Prehistoric Creatures. Hermes House: London.

[FS15] Faurby, S., & J.-C. Svenning. 2015. A species-level phylogeny of all extant and late Quaternary extinct mammals using a novel heuristic-hierarchical Bayesian approach. Molecular Phylogenetics and Evolution 84: 14–26.

[FP64] Fisher, J., & R. T. Peterson. 1964. The World of Birds: A comprehensive guide to general ornithology. Macdonald: London.

[TS88] Tassy, P., & J. Shoshani. 1988. The Tethytheria: elephants and their relatives. In: Benton, M. J. (ed.) The Phylogeny and Classification of the Tetrapods vol. 2. Mammals pp. 283–315. Clarendon Press: Oxford.

Last updated: 15 August 2018.

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