''Miniochoerus'' is an extinct
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 small
oreodont
Merycoidodontoidea, previously known as "oreodonts" or " ruminating hogs," are an extinct superfamily of prehistoric cud-chewing artiodactyls with short faces and fang-like canine teeth. As their name implies, some of the better known forms we ...
endemic to
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 ...
. They lived during the
Late Eocene
The Priabonian is, in the International Commission on Stratigraphy, ICS's geologic timescale, the latest age (geology), age or the upper stage (stratigraphy), stage of the Eocene epoch (geology), Epoch or series (stratigraphy), Series. It spans ...
to
Early Oligocene
The Rupelian is, in the geologic timescale, the older of two age (geology), ages or the lower of two stage (stratigraphy), stages of the Oligocene epoch (geology), Epoch/series (stratigraphy), Series. It spans the time between . It is preceded b ...
38–30.8
mya, existing for approximately .
Fossils have been found only in
North Dakota
North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minneso ...
,
South Dakota
South Dakota (; Sioux language, Sioux: , ) is a U.S. state, state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Dakota people, Dakota Sioux ...
,
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 ...
,
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 ...
, and
Wyoming
Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...
.
Species
*''M. affinis'' (syn. ''Merycoidodon platycephalus'', ''M. battlecreekensis'', ''Oreodon coloradoensis'', ''Stenopsochoerus sternbergi'')
*''M. chadronensis'' (syn. ''Parastenopsochoerus conversensis'', ''Stenopsochoerus douglasensis'', ''S. reideri'')
*''M. forsythae''
*''M. gracilis''
*''M. starkensis'' (syn. ''M. cheyennensis'', ''M. helprini'', ''M. nicholsae'', ''M. ottensi'', ''Platyochoerus hatcreekensis'', ''P. heartensis'', ''Stenopsochoerus berardae'', ''S. joderensis'')
Description

Typically, there were about the size of a small
dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers. ...
. Their
skull
The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate.
In the human, the skull comprises two prominent ...
s were small and short, compared to other oreodont species, many of which had proportionately large heads. Unlike other oreodont species, they had small
canine
Canine may refer to:
Zoology and anatomy
* Animals of the family Canidae, more specifically the subfamily Caninae, which includes dogs, wolves, foxes, jackals and coyotes
** ''Canis'', a genus that includes dogs, wolves, coyotes, and jackals
** Do ...
s which would have done little good against foes. The genus arose during the late
Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...
, and survived the Late Eocene
extinction
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 ...
event, giving rise to a dwarfed
lineage during the early
Oligocene
The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...
.
References
{{Taxonbar, from=Q6865644
Oreodonts
Oligocene Artiodactyla
Eocene Artiodactyla
Paleogene mammals of North America
Fossil taxa described in 1956
Prehistoric Artiodactyla genera
Oligocene mammals of North America