''Tomarctus'' is a

canid Canidae (; from Latin, ''canis'', "dog") is a family (biology), biological family of caniform carnivorans, constituting a clade. A member of this family is also called a canid (). The family includes three subfamily, subfamilies: the Caninae, a ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of the

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Borophaginae The extinct Borophaginae form one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct Hesperocyoninae and extant Caninae. Borophaginae, called "bone-crushing dogs", were endemic to North America d ...

which inhabited most of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

during the late

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to ...

to the Early Barstovian age of the

Middle Miocene The Middle Miocene is a sub-epoch of the Miocene epoch (geology), epoch made up of two Stage (stratigraphy), stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene. The sub-epoch lasted from 15.97 ± 0. ...

(23—16 million years ago). ''Tomarctus'' existed for approximately . This animal shared a period and ecology with a variety of

bear dog Amphicyonidae is an extinct family of terrestrial carnivorans belonging to the suborder Caniformia. They first appeared in North America in the middle Eocene (around 45 mya), spread to Europe by the late Eocene (35 mya), and further spread to A ...

s, giant

mustelid The Mustelidae (; from Latin , weasel) are a diverse family of carnivoran mammals, including weasels, badgers, otters, polecats, martens, grisons, and wolverines. Otherwise known as mustelids (), they form the largest family in the suborde ...

genera, and the genus of bone-crushing Canidae, ''

Cynarctoides ''Cynarctoides'' is an extinct genus of the Borophaginae subfamily of canids native to North America. It lived from the Early Oligocene to the Middle Miocene, 33.3—13.6 Mya, existing for approximately . Seven species are currently recognised, ...

''. As the bear dogs and giant mustelids became extinct, ''Tomarctus'' were a

hyena Hyenas or hyaenas ( ; from Ancient Greek , ) are feliform carnivoran mammals belonging to the family Hyaenidae (). With just four extant species (each in its own genus), it is the fifth-smallest family in the order Carnivora and one of the sma ...

-like fruit-eating canidae.

Species

The genus currently contains two accepted species, ''Tomarctus brevirostris'' and ''Tomarctus hippophaga''. ''Tomarctus brevirostris'', synonymous with ''Aelurodon francisi'', was named by

Edward Drinker Cope Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American zoologist, paleontology, paleontologist, comparative anatomy, comparative anatomist, herpetology, herpetologist, and ichthyology, ichthyologist. Born to a wealthy Quaker fam ...

in 1873. Fossil specimens have been found as far south as

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

, east to Plum Point,

Maryland Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east ...

, west to

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, and north to

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

.Paleobiology Database: Tomarctus brevirostris
/ref> ''Tomarctus hippophaga'' was first described by Matthew and Cook in 1909 from the Trojan Quarry,

Olcott Formation The Olcott Formation is a geologic formation in Nebraska. It preserves fossils dating to the Barstovian stage of the Neogene period. See also * List of fossiliferous stratigraphic units in Nebraska * Paleontology in Nebraska The location of ...

Nebraska Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Ka ...

. Specimens have since been found as far west as

and as far north as the

Alberta, Canada Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

line.Paleobiology Database: Tomarctus hippophaga
/ref> Tomarctus brevirostris

References

*Martin, L.D. 1989. Fossil history of the terrestrial carnivora. Pages 536 - 568 in J.L. Gittleman, editor. Carnivore Behavior, Ecology, and Evolution, Vol. 1. Comstock Publishing Associates: Ithaca. *Tedford, R.H. 1978. History of dogs and cats: A view from the fossil record. Pages 1 – 10 in Nutrition and Management of Dogs and Cats. Ralston Purina Co.: St. Louis.
- Bio One Data Base - Tomarctus
Borophagines Miocene canids Serravallian extinctions Prehistoric mammals of North America Prehistoric carnivoran genera Burdigalian first appearances Taxa named by Edward Drinker Cope Fossil taxa described in 1873 {{canid-stub