Hesperocyoninae

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in biology, The extinct Hesperocyoninae are one of three subfamilies found within the canid family. he other two canid subfamilies are the extinct Borophaginae and extant Caninae.

An analysis of the fossil record of North American fossil carnivores shows that competition from felids and borophagines led to a near-extinction decline in hesperocionin from about 20 million years ago to 10 million years ago. It has been found.

Scientific classification

Alias:: Hesperocyoninae

Protection level:: 8

Domain:: Eukaryota

Kingdom:: Animalia

Phylum:: Chordate

Class:: Class Mammalia

Order:: Carnivora

Family:: Canidae

Subfamily:: Hesperocyoninae

Mode Of Reproduction:: Viviparous

Reproductive Form:: Sexual Reproduction

Taxonomic History

Hesperocyoninae was named by Martin (1989). The members of this subfamily were reassigned to the family Canidae (with no subfamily) by Xiaoming Wang in 1999.

Hesperocyoninae are basal canids that gave rise to the other canid groups, including the Borophaginae and Caninae according to Wang and Tedford.

This disused subfamily were endemic to North America living from the Duchesnean stage of the Late Eocene through the early Barstovian stage of the Miocene lasting around 20 million years. It comprises a total of 10 recognized genera and 26 recognized species; among these, 4 genera and 8 species are new. Four major lineages can be defined based on shared characteristics:

Mesocyon-Enhydrocyon clade (includes Cynodesmus, Sunkahetanka, Philotrox)
Osbornodon clade
Paraenhydrocyon
Ectopocynus clade

The genus Caedocyon, which is only known from a single partial cranium that shows some Paraenhydrocyon affinities, probably represents another independent lineage.

Hesperocyon, which lacks the shared derived characters that would include it within any of the aforementioned clades, is possibly ancestral to many of the lineages. Some evidence indicates the Paraenhydrocyon clade may be directly descended from Hesperocyon gregarius. According to Xiaoming Wang, Hesperocyon coloradensis provides an important link between H. gregarius and the Mesocyon-Enhydrocyon clade.

Extinction

According to an analysis of the fossil record of North American fossil carnivorans, the decline of hesperocyonines to extinction during the period from about 20 to 10 million years ago was driven by competition with felids and borophagines.