Elephantidae

The African forest elephant Loxodonta africana cyclotis, treated by some as a separate species. Photo 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).

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
            `--+--Loxodonta Cuvier 1825 TS88, 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
               `--+--Elephas TS88
                  `--Mammuthus Burnett 1830 TS88, CM78 [incl. Archidiskodon Pohlig 1888 CM78]
                       |--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, C76, Parelephas columbi CM78]
                                `--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 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==

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

[C76] Cope, E. D. 1876. 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 Evolution of African Mammals (V. J. Maglio & H. B. S. Cooke, eds) pp. 336-367. Harvard University Press: Cambridge (Massachusetts).

[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 The Phylogeny and Classification of the Tetrapods, vol. 2. Mammals (M. J. Benton, ed.) pp. 283-315. Clarendon Press: Oxford.

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