Hesperocyoninae
Encyclopedia
Hesperocyoninae is a subfamily of extinct canids.

Taxonomic history

Hesperocyoninae was named by Martin (1989). The members of this subfamily were reassigned to the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Canidae
Canidae
Canidae is the biological family of carnivorous and omnivorous mammals that includes wolves, foxes, jackals, coyotes, and domestic dogs. A member of this family is called a canid . The Canidae family is divided into two tribes: Canini and Vulpini...

 (with no subfamily) by Xiaoming Wang
Xiaoming Wang
Xiaoming Wang is a noted paleontologist and geologist born in People's Republic of China living in the United States.-Area of expertise:Dr. Wang specializes in the fossil evolution, systematics, and phylogeny of mammals of the Cenozoic...

 in 1999.

Hesperocyoninae are basal canids that gave rise to the other canid groups, including the Borophaginae
Borophaginae
The subfamily Borophaginae is an extinct group of canids called "bone crushing dogs" that were endemic to North America during the Oligocene to Pliocene and lived roughly 36—2.5 million years ago and existing for approximately .-Origin:...

 and Caninae
Caninae
Caninae is the only living subfamily of Canidae. Many extinct species of Caninae were endemic to North America, living from 34 Ma—11,000 years ago. Some members of the endemic North American canines survived to the present time. This subfamily was recently revised by Tedford, Wang, and Taylor...

 according to Wang and Tedford.

This disused subfamily were endemic to North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 living from the Duchesnean
Duchesnean
The Duchesnean North American Stage on the geologic timescale is a North American Land Mammal Age , with an age from 42 to 38 million years BP, representing . It falls within the Eocene epoch. The Duchesnean is preceded by the Uintan and followed by the Chadronian NALMA.The Duchesnean falls within...

 stage of the Late Eocene through the early Barstovian
Barstovian
The Barstovian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology , typically set from 16,300,000 to 13,600,000 years BP, a period of . It is usually considered to overlap the Langhian and Serravallian...

 stage of the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...

 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
    Mesocyon
    Mesocyon is an extinct genus of terrestrial carnivore within the family Canidae, subfamily Hesperocyoninae, which inhabited North America from the Early Oligocene 33.9—20.6 Ma, existing for approximately ....

    -Enhydrocyon
    Enhydrocyon
    Enhydrocyon is an extinct genus of bone crushing dog which inhabited North America exclusively during the Oligocene living from around 28.7—22.0 Ma and existed for approximately ....

    clade
    Clade
    A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

  • Osbornodon
    Osbornodon
    Osbornodon is an extinct genus of bone-crushing canid that were endemic to North America and which lived from the Orellan age of the Early Oligocene to Early Miocene epoch 33.9—15.97 Ma and existed for approximately ....

    clade
  • Paraenhydrocyon
    Paraenhydrocyon
    Paraenhydrocyon is an extinct genus of bone crushing omnivorous mammal similar to a dog of the family Canidae which inhabited North America during the Oligocene living from 33.3—20.6 Ma and existed for approximately ....

  • Ectopocynus
    Ectopocynus
    Ectopocynus is an extinct genus of small bone crushing carnivorous mammal similar to a dog of the family Canidae) which inhabited North America during the Oligocene living from 33.3—16.0 Ma and existed for approximately ....

     clade


The Caedocyon
Caedocyon
Caedocyon is an extinct genus of bone crushing omnivorous mammal similar to a dog of the family Canidae) which inhabited western North America during the Oligocene living from 30.8—20.6 Ma and existed for approximately ....

probably forms a distinct clade of its own.

Hesperocyon
Hesperocyon
Hesperocyon is an extinct genus of canids, family of Canidae and subfamily Hesperocyoninae which was endemic to North America from southern Canada to appearing during the Uintan age-Bridgerian age of the Mid-Eocene 42.5 mya—31.0 Ma. . Hesperocyon existed for approximately .-Taxonomy:Hesperocyon...

is possibly ancestral to many of the lineages and lacks the shared derived characters
which would included it within any of the aforementioned clades. There is evidence that the Paraenhydrocyon
Paraenhydrocyon
Paraenhydrocyon is an extinct genus of bone crushing omnivorous mammal similar to a dog of the family Canidae which inhabited North America during the Oligocene living from 33.3—20.6 Ma and existed for approximately ....

clade may be directly descendant from Hesperocyon H. gregarius. According to Xiaoming Wang
Xiaoming Wang
Xiaoming Wang is a noted paleontologist and geologist born in People's Republic of China living in the United States.-Area of expertise:Dr. Wang specializes in the fossil evolution, systematics, and phylogeny of mammals of the Cenozoic...

, Hesperocyon H. coloradensis provides an important link between H. gregarius and the Mesocyon-Enhydrocyon clade.
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