''Protanancus'' is an extinct

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of amebelodontid proboscidean from

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and

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. The genus consists solely of type species ''P. macinnesi''.Anancus'', and the Greek ''prōtos'' "first".

Description

''Protanancus'', about the size of a present-day

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, was presumably quite similar to the related proboscidean '' Platybelodon''. Like ''Platybelodon'', the mandibular symphysis of this species was narrow and elongated, and possessed two flattened tusks. Investigation of the structure of the lower tusks revealed that those of ''Protanancus'' were concentric, like those of most proboscideans (including present-day proboscideans), while those of ''Platybelodon'' possessed dentinal tubules.

Classification

''Protanancus'' was described by Arambourg in 1945.Siwaliks area. This animal is thought to have evolved from ''Gomphotherium'', and developed over millions of years to give rise to other similar animals such as ''Platybelodon'' or '' Amebelodon''. ''Protanancus'' is also related to '' Archaeobelodon''. Other fossils have been found in

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Paleobiology

Fossils of ''Protanancus'' in China have been found in the same locations as those of ''Platybelodon''. However, it appears that after living together for at least two million years, ''Platybelodon'' survived and ''Protanancus'' became extinct. Only in the area where ''Platybelodon'' was not present (the Siwalik) did ''Protanancus'' still thrive. The shape of the jaws of the two animals indicates that they had the same lifestyle, with shovel-like tusks that could pick up plant material. However, the tubular structure of ''Platybelodon's'' tusks indicates that this animal bore greater loads and more abrasion than ''Protanancus''.Shiqi Wang, Tao Deng, Tao Tang, Guangpu Xie, Yuguang Zhang, and Duoqing Wang. (2015) Evolution of Protanancus (Proboscidea, Mammalia) in East Asia. Journal of Vertebrate Paleontology 35:1.

References

{{Taxonbar, from=Q20721964 Prehistoric placental genera Amebelodontidae Miocene proboscideans Miocene first appearances Miocene extinctions