Neotherium

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Neotherium
Temporal range: Middle Miocene
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Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Clade: Pinnipedia
Family: Odobenidae
Genus: Neotherium
Kellogg, 1931
Species:
N. mirum
Binomial name
Neotherium mirum
Kellogg, 1931

Neotherium mirum is an extinct species of basal walrus. [1] [2] It was smaller than living forms and it did not have long tusks. Males were larger than females.

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Kolponomos is an extinct genus of carnivoran mammal that existed in the Late Arikareean North American Land Mammal Age, early Miocene epoch, about 20 million years ago. It was likely a marine mammal. The genus was erected in 1960 by Ruben A. Stirton, a paleontologist at the University of California Museum of Paleontology, Berkeley, for the species K. clallamensis, on the basis of a partial skull and jaw found on the Olympic Peninsula. At the time, Stirton questionably assigned it to Procyonidae, its systematic position remained problematic until the discovery of more fossils including a nearly complete cranium from the original locality of K. clallamensis which helped identify it as part of the group from which pinnipeds evolved.

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References

  1. Naoki Kohno, Lawrence G. Barnes & Kiyoharu Hirota (1994). "Miocene fossil pinnipeds of the genera Prototaria and Neotherium (Carnivora; Otariidae; Imagotariinae) in the North Pacific Ocean: Evolution, relationships and distribution". The Island Arc . 3 (4): 285–308. doi:10.1111/j.1440-1738.1994.tb00117.x.
  2. Berta, Annalisa. 2002b. Pinniped Evolution in Encyclopedia of Marine Mammals, eds. Perrin, William F., Bernd Würsig, and J. G. M. Thewissen. Academic Press.