''Allodesmus'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

pinniped Pinnipeds (pronounced ), commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant families Odobenidae (whose only living member is the walru ...

from the middle to late

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

that belongs to the

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

pinniped

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Desmatophocidae Desmatophocidae is an extinct family of pinnipeds closely related to the eared seals and walruses. ''Allodesmus'' measured about long and weighed . ''Allodesmus'' had the specific anatomical features found in modern polygynous pinnipeds:

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

, strong canines for fights between bulls and teeth with well-defined growth zones, a result from periodic fasting (in order to defend their

harem Harem (Persian: حرمسرا ''haramsarā'', ar, حَرِيمٌ ''ḥarīm'', "a sacred inviolable place; harem; female members of the family") refers to domestic spaces that are reserved for the women of the house in a Muslim family. A hare ...

, males would not take to the sea to feed during the breeding season).

Taxonomy

''Allodesmus sinanoensis'' and ''A. packardi'' were previously assigned separate genera, ''Megagomphos'' and ''Brachyallodesmus'', respectively, but many authors questioned this generic distinction, and the cladistic analysis by Boessenecker and Churchill (2018) found no support for this generic scheme. '' Atopotarus'', referred to ''Allodesmus'' by some authors (e.g. Mitchell 1966), is distinct from ''Allodesmus'' by the absence of a prenarial shelf and M2, double-rooted cheek teeth, a small, triangular postorbital process, and a mastoid process projecting ventral to the postglenoid process.Robert W. Boessenecker; Morgan Churchill (2018). "The last of the desmatophocid seals: a new species of Allodesmus from the upper Miocene of Washington, USA, and a revision of the taxonomy of Desmatophocidae". Zoological Journal of the Linnean Society. Online edition. doi:10.1093/zoolinnean/zlx098.

References

* Encyclopedia of Marine Mammals, ed. William F. Perrin,

Bernd Würsig Bernd Gerhard Würsig (born 9 November 1948 in Barsinghausen, Germany)"Bernd Gerhard Würsig". Marqui's Who's Who in the World. 2012. 29th Edition. is an educator and researcher who works mainly on aspects of behavior and behavioral ecology of ...

, J.G.M. Thewissen

External links

Miocene pinnipeds Fossils of Japan Fossils of the United States Fossil taxa described in 1922 Miocene California Prehistoric carnivoran genera {{paleo-carnivora-stub