Kawas benegasorum

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Kawas benegasorum
Temporal range: Mid Miocene
14–12  Ma
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Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Clade: Pinnipedia
Family: Phocidae
Genus: Kawas
Cozzuol, 2001
Species:
K. benegasorum
Binomial name
Kawas benegasorum
Cozzuol, 2001 [1]

Kawas is an extinct genus of phocid from the Miocene of Argentina. It contains a single species known as Kawas benegasorum.

Contents

Etymology

Kawas comes from the Tehuelche language and is the feminine form of 'Kawa' (elephant seal). 'Kawas' can also be translated to mean 'mermaid'. [2]

Description

Kawas was described from an articulated partial skeleton that has been dated to the middle Miocene around 12-14 million years ago. The skeleton is notable by the fact that it shares features in common with "northern hemisphere" seals (Phocinae) then it does other seals from the southern hemisphere, all traditionally placed in the subfamily Monachinae. This may suggest the Monachinae is paraphyletic. [2]

Another notable aspect of Kawas is the discovery of preserved gut content, which indicate a diet primarily of bony fish. It is one of only two fossil pinnipeds with preserved content. [3]

Related Research Articles

Earless seal Family of mammals

The earless seals, phocids or true seals are one of the three main groups of mammals within the seal lineage, Pinnipedia. All true seals are members of the family Phocidae. They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Otariidae. Seals live in the oceans of both hemispheres and, with the exception of the more tropical monk seals, are mostly confined to polar, subpolar, and temperate climates. The Baikal seal is the only species of exclusively freshwater seal.

The Miocene is the first geological epoch of the Neogene Period and extends from about 23.03 to 5.333 million years ago (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words μείων and καινός and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene is preceded by the Oligocene and is followed by the Pliocene.

Eared seal Marine mammals in the family Otariidae

An eared seal or otariid or otary is any member of the marine mammal family Otariidae, one of three groupings of pinnipeds. They comprise 15 extant species in seven genera and are commonly known either as sea lions or fur seals, distinct from true seals (phocids) and the walrus (odobenids). Otariids are adapted to a semiaquatic lifestyle, feeding and migrating in the water, but breeding and resting on land or ice. They reside in subpolar, temperate, and equatorial waters throughout the Pacific and Southern Oceans and the southern Indian and Atlantic Oceans. They are conspicuously absent in the north Atlantic.

Pinniped Infraorder of mammals

Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals in the clade Pinnipedia. They comprise the extant families Odobenidae, Otariidae, and Phocidae. There are 34 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage. Pinnipeds belong to the order Carnivora; their closest living relatives are musteloids, having diverged about 50 million years ago.

Bearded seal Species of Arctic dwelling marine mammal

The bearded seal, also called the square flipper seal, is a medium-sized pinniped that is found in and near to the Arctic Ocean. It gets its generic name from two Greek words that refer to its heavy jaw. The other part of its Linnaean name means bearded and refers to its most characteristic feature, the conspicuous and very abundant whiskers. When dry, these whiskers curl very elegantly, giving the bearded seal a "raffish" look.

Caniformia Suborder of mammals

Caniformia is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include dogs, bears, raccoons, and mustelids. The Pinnipedia are also assigned to this group. The center of diversification for the Caniformia is North America and northern Eurasia. Caniformia stands in contrast to the other suborder of Carnivora, the Feliformia, the center of diversification of which was in Africa and southern Asia.

Groß Pampau Municipality in Schleswig-Holstein, Germany

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Phocinae Subfamily of carnivores

Phocinae is a subfamily of Phocidae whose distribution is found in the seas surrounding the Holarctic, with the Baikal seal being the world's only freshwater species of pinniped. What distinguishes them from other phocid seals is the presence of well-developed claws on their front and back flippers. The Phocinae is divided into three extant tribes: Erignathini, Cystophorini, and Phocini. Members of both Erignathini and Cystophorini have 34 chromosomes, while species in the tribe Phocini have 32 chromosomes.

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Dryolestida Extinct order of mammals

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<i>Livyatan</i> Extinct genus of sperm whale from the Miocene epoch

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Leptophoca is an extinct genus of earless seals from the North Atlantic realm.

<i>Piscobalaena</i> Extinct genus of mammals

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<i>Huilatherium</i> Extinct genus of leontiniid, a group of hoofed mammals

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Monotherium is an extinct genus of phocid belonging to the subfamily Monachinae. It is known from fossils found in the middle to late Miocene of Belgium.

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Callophoca is an extinct genus of earless seals from the late Miocene to early Pliocene of Belgium and the US Eastern Seaboard.

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References

  1. Kawas benegasorum at fossilworks.org (retrieved 26 July 2022)
  2. 1 2 Cozzuol, Mario A. (2001). "A "Northern" Seal from the Miocene of Argentina: Implications for Phocid Phylogeny and Biogeography". Journal of Vertebrate Paleontology. 21 (3): 415–421.
  3. Berta, Annalisa (2017). The Rise of Marine Mammals: 50 Million Years of Evolution. Johns Hopkins University Press. p. 106. ISBN   9781421423265.