Stegodibelodon

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Stegodibelodon
Temporal range: Early Pliocene
~5–4  Ma
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Stegodibelodon schneideri mandible.JPG
S. schneideri mandible
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Proboscidea
Family: Elephantidae
Genus: Stegodibelodon
Coppens, 1972
Type species
Stegodibelodon schneideri
Coppens, 1972

Stegodibelodon is an extinct genus primitive elephantid known from the Early Pliocene of Africa. It is known only from the Djourab region of northern Chad, where it was discovered in 1964 by the hydrogeologist Jean-Louis Schneider. [1] It differs from the most primitive elephantid Stegotetrabelodon by the absence of lower tusks and a shortened mandibular symphysis, and the more pronounced nature of the lamellae on the molars (with the median sulcus being absent), with each molar possessing at least seven lamellae, though the number of lamellae is low compared to modern elephant teeth, and the teeth are also low crowned (brachydont) relative to modern elephants. [2]

The genus Stegodibelodon and the species Stegodibelodon schneideri were described in 1972 by Yves Coppens. [1] This genus has three referenced fossil collections, one from the Pliocene in Chad and two from the Miocene to Pliocene in Ethiopia. [3] The genus is not well known and opinions differ on whether it is a "true elephant" or not. [4]

Stegodibelodon schneideri is only known from the Djourab region in northern Chad where numerous fossils were unearthed on three sites in the Toros-Menalla fossil sector in 1964 and then from 1998. [5]

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References

  1. 1 2 Yves Coppens, 1972. Un nouveau proboscidien du Pliocène du Tchad, Stegodibelodon schneideri nov. gen. nov. sp., et le phylum des Stegotetrabelodontinae, Comptes Rendus de l'Académie de Sciences de Paris, Série D, 274, pp. 2962-2965.
  2. Athanassiou, Athanassios, 2022. The Fossil Record of Continental Elephants and Mammoths (Mammalia: Proboscidea: Elephantidae) in Greece, in: Vlachos, E. (eds) Fossil Vertebrates of Greece Vol. 1. Springer, Cham. pp. 345-391.
  3. Stegodibelodon. Coppens 1972 (elephant)
  4. van der Made, J. 2014. The large mammals of the Plio-Pleistocene of Africa: Afrotheria, Perissodactyla and Artiodactyla, inLa Cuna de la Humanidad pp. 324-336, edited by: Enríquez, S. and Alvarado, E., Museo Arquelógico Regional, Alcalá de Henares & Museo de la Evolución Humana.
  5. Mackaye Hassan Taïsso, 2001. Les Proboscidiens du mio-pliocène du Tchad : biodiversité, biochronologie, paléoécologie et paléobiogéographie. Thesis, Chapter III, pp. 163-175, Plates 12-15.