Miniochoerus

Miniochoerus Temporal range: Late Eocene–Oligocene PreЄ Є O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
Class:	Mammalia
Order:	Artiodactyla
Family:	†Merycoidodontidae
Subfamily:	†Miniochoerinae
Genus:	†Miniochoerus Schultz and Falkenbach, 1956
Type species
Miniochoerus battlecreekensis
Species[1]
see text
Synonyms
Paraminiochoerus Schultz and Falkenbach, 1956[2] Parastenopsochoerus Schultz and Falkenbach, 1956 Platyochoerus Schultz and Falkenbach, 1956 Pseudostenopsochoerus Schultz and Falkenbach, 1956[2] Stenopsochoerus Schultz and Falkenbach, 1956

Miniochoerus is an extinct genus of small oreodont endemic to North America during the Late Eocene through Early Oligocene (38—30.8 mya) which existed for approximately 6 million years.^[1][3]

Taxonomy

Miniochoerus was named by Schultz and Falkenbach (1956). Its type is Miniochoerus battlecreekensis. It was synonymized subjectively with Oreonetes by Lander (1998). It was assigned to Merycoidodontidae by Schultz and Falkenbach (1956) and Stevens and Stevens (1996).^[4][5]

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)

Morphology

Typically, there were about the size of a small dog. Their skulls were small and short, compared to other oreodont species, many of which had proportionately large heads. Unlike other oreodont species, they had small canines which would have done little good against foes. The genus arose during the late Eocene, and survived the Late Eocene extinction event, giving rise to a dwarfed lineage during the early Oligocene.^[6]

A single specimen was examined by M. Mendoza for body mass and estimated to have a weight of 32.4 kg (71.4 lbs).^[7]

Fossil distribution

Fossil distribution is confined to North Dakota, South Dakota, Nebraska, Montana, and Wyoming.

References

1. Stevens, M.S.; Stevens, J.B. (1996). "Merycoidodontinae and Miniochoerinae". In Prothero, D.R.; Emry, R.J. The terrestrial Eocene-Oligocene transition in North America. Cambridge: Cambridge University Press. pp. 498–573. ISBN 0-521-43387-8.
2. Subgenus not recognized by Stevens and Stevens.
3. PaleoBiology Database: Miniochoerus, basic info
4. C. B. Schultz and C. H. Falkenbach. 1956. Bulletin of the American Museum of Natural History 109
5. B. Lander. 1998. Oreodontoidea. In C. M. Janis, K. M. Scott, and L. L. Jacobs (eds.), Evolution of Tertiary mammals of North America 402-425
6. Prothero, D.R. (2006). After the Dinosaurs: The Age of Mammals. Indiana University Press. ISBN 0-253-34733-5.
7. M. Mendoza, C. M. Janis, and P. Palmqvist. 2006. Estimating the body mass of extinct ungulates: a study on the use of multiple regression. Journal of Zoology