Pontolis
Temporal range: Miocene-Pliocene
Skull (LACM 162551) of P. barroni, Natural History Museum of Los Angeles County
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Clade: Pinnipedia
Family: Odobenidae
Genus: †Pontolis
True, 1905
Type species
†Pontolis magnus
True, 1905
Species
  • †P. magnus (True, 1905, type]
  • †P. barroni Biewer, Velez-Juarbe & Parham, 2020
  • †P. kohnoi Biewer, Velez-Juarbe & Parham, 2020
Synonyms

Pontoleon magnus True, 1905

Pontolis is an extinct genus of large walrus. It contained three species, P. magnus, P. barroni, and P. kohnoi.[1][2] Like all pinnipeds, Pontolis was a heavily built amphibious carnivore. Pontolis lived along the Pacific coast of North America along what is now the western coasts of California and Oregon between 11.608 and 5.332 million years ago, during the Miocene and Pliocene.[1]

Description

Jaw of P. magnus

The skull of Pontolis is 60 cm (24 in) long, surpassing skulls of any other prehistoric pinnipeds and twice as big as the skulls of modern male walruses.[3] This giant species was much larger than modern walrus, though like many other extinct walrus species, its upper canines did not develop into long tusks like those of the modern walrus. Pontolis reached more than 4 m (13 ft) in body length,[4] rivaling the extant southern elephant seal as the largest pinniped[5] and member of the order Carnivora of all time. Weight estimates for Pontolis range between 2,000 to 4,000 kg (4,400 to 8,800 lb).[6]

References

  1. ^ a b "Pontolis". Fossilworks. Retrieved 17 December 2021.
  2. ^ Biewer, Jacob N.; Velez-Juarbe, Jorge; Parham, James F. (1 December 2020). "Insights on the Dental Evolution of Walruses Based on New Fossil Specimens from California". Journal of Vertebrate Paleontology. 40 (5): e1833896. Bibcode:2020JVPal..40E3896B. doi:10.1080/02724634.2020.1833896. ISSN 0272-4634. S2CID 228814992.
  3. ^ Annalisa Berta (2017). The Rise of Marine Mammals: 50 Million Years of Evolution. Johns Hopkins University Press. p. 110. ISBN 9781421423258. Retrieved 21 August 2022.
  4. ^ Morgan Churchill, Mark T. Clementz, Naoki Kohno. "Cope’s rule and the evolution of body size in Pinnipedimorpha (Mammalia: Carnivora)". Evolution. 2015 Jan;69(1):201-15. doi:10.1111/evo.12560
  5. ^ Xénia Keighley, Morten Tange Olsen, Peter Jordan, Sean P.A. Desjardins (2021). The Atlantic Walrus: Multidisciplinary Insights into Human-Animal Interactions. Charlotte Cockle. p. 17. ISBN 9780128174319. Retrieved 21 August 2022.((cite book)): CS1 maint: multiple names: authors list (link)
  6. ^ Valentin, T. Encyclopedia Largest Prehistoric Animals Vol.1 Vertebrates part1 Mammals ch.1 Carnivores - Hyaenidae, Mustelids and Viverrids Encyclopedia Largest prehistoric animals Vol.1 Vertebrates part1 Mammals ch.1 Carnivores -Mesonychids.


Categories