Euoplocyon is an extinct genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of 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 a small terrestrial

Terrestrial animal

Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...

 canine

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...

 which inhabited most of 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...

 during the Hemingfordian stage of the Early Miocene

Early Miocene

The Early Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages....

 subepoch through the 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 Middle Miocene

Middle Miocene

The Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene....

 subepoch living 20.6—13.6 Mya, existing for about .

Taxonomy

Euoplocyon was named by Matthew (1924). Its type is Euoplocyon praedator. It was assigned to Canidae by Matthew (1924) and Munthe (1998); and to Borophagini by Wang et al. (1999).

Morphology

Fossil specimens of two individuals' body mass were examined by Legendre and Roth. The first specimen was estimated to weigh 9.63 kg (21.2 lbs). The second specimen was estimated to weigh 9.13 kg (20.1 lbs).

Species

• E. brachygnathus (synonymous with E. praedator) was incorrectly named Aelurodon brachygnathus by Douglass in 1903 according to Wang.
• E. spissiden was originally named Aelurocyon spissidens by White in 1947. It was recombined as Enhydrocyon spissidens by Olsen in 1958 and Euoplocyon spissidens by Tedford and Frailey (1976) and X. Wang in 1999.

Sister genera

Cormocyon

Cormocyon

Cormocyon is an extinct genus of the Borophaginae and a terrestrial canine which inhabited most of North America during the Geringian stage of the Paleogene through Harrisonian stage of the Oligocene epoch living 30.8—20.6 Mya, existing for about ....

, Desmocyon

Desmocyon

Desmocyon is an extinct genus of the Borophaginae and a terrestrial canine which inhabited most of North America during the Harrisonian stage of the Late Oligocene through Early Hemingfordian stage of the Early Miocene epoch living 24.8—16.3 Mya existing for approximately .-Fossil record:It is a...

, Metatomarctus

Metatomarctus

Metatomarctus is an extinct genus of Borophaginae and a terrestrial canine which inhabited most of North America during the Early Hemingfordian stage of the Miocene epoch living 23.0—5.3 Mya, existing for approximately -Taxonomy:...

, Microtomarctus

Microtomarctus

Microtomarctus is an extinct genus of the Borophaginae and a small terrestrial canine which inhabited most of North America during the Whitneyan stage of the Early Miocene subepoch through the Barstovian stage of the Middle Miocene subepoch.Microtomarctus existed for approximately .Like other...

, Protomarctus

Protomarctus

Protomarctus is an extinct member of the Borophaginae and a small terrestrial canine which inhabited most of North America during the Burdigalian stage of the Miocene epoch 20.4—15.9 Mya, existing for approximately .-Taxonomy:...

, Psalidocyon

Psalidocyon

Psalidocyon is an extinct genus of the Borophaginae and a small terrestrial canine which inhabited most of North America during the Hemingfordian stage of the Early Miocene subepoch through the Barstovian stage of the Middle Miocene subepoch 20.6—13.6 Ma, existing for about ..-Morphology:Fossil...

, and Tephrocyon

Tephrocyon

Tephrocyon is an extinct genus of the Borophaginae and a small to medium sized terrestrial canine which inhabited most of North America during the Barstovian stage of the Middle Miocene 16.3—13.6 Ma, existing for approximately .-Morphology:...

.

Fossil distribution

• E. brachygnathus was found in the Flint Creek Beds, a Miocene terrestrial horizon in Montana
  Montana
  Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
  
  .
• E. spissiden was found on the Thomas Farm in a Hemingfordian terrestrial in the Alachua Formation, Alachua County, Florida
  Alachua County, Florida
  Alachua County is a county located in the U.S. state of Florida. The U.S. Census Bureau 2006 estimate for the county is 227,120. Its county seat is Gainesville, Florida. Alachua County is the home of the University of Florida and is also known for its diverse culture, local music, and artisans...
  
  .

Sources

• zipcodezoo.com
• Flynn, J.J., 1998. Early Cenozoic Carnivora ("Miacoidea"). pp.110-123 in C.M. Janis, K.M. Scott, and L.L. Jacobs (eds.) Evolution of Tertiary Mammals of North America. Volume 1: Terrestrial Carnivores, Ungulates, and Ungulatelike Mammals. Cambridge University Press, Cambridge. ISBN 0-521-35519-2