Leptomeryx Temporal range: middle Eocene to Late Oligocene[1]
Skeleton, Paleontology Museum of Zurich
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Family:	†Leptomerycidae
Subfamily:	†Leptomerycinae
Genus:	†Leptomeryx Leidy, 1853
Type species
†Leptomeryx evansi
Species[2]
†L. blacki †L. evansi †L. mammifer †L. obliquidens †L. speciosus †L. yoderi

Leptomeryx is an extinct genus of ruminant of the family Leptomerycidae, endemic to North America during the Eocene through Oligocene 38–24.8 Mya, existing for approximately 13.2 million years. It was a small deer-like ruminant with somewhat slender body.

Mounted skeleton

L. evansi

Fossil distribution

Sites and species recovered:

• Titus Canyon, Inyo County, California (L.blacki) ~30.6—33.9 Ma.
• UNSM Sx-8 (Orella C), Sioux County, Nebraska (L. elissae) ~33.9—24.8 Ma.
• Anxiety Butte, Saskatchewan, Canada (L. sp., L. evansi) ~38—24.8 Ma.
• Calf Creek, Saskatchewan, Canada, (L. mammifer) ~38—33.3 Ma.
• Toadstool Park, Sioux County, Nebraska (L. speciosus) ~37.2—33.3 Ma.^[3]
• Medicine Pole Hills, Bowman County, North Dakota (L. yoderi) ~38—33.9 Ma.^[4]

References

• Webb, S.D., 1998. Hornless ruminants. pp. 463–476 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
• Heaton, T.H. and Emry, R.J., 1996. Leptomerycidae pp. 581–608 in D.R. Prothero and R.J. Emry (eds.) The Terrestrial Eocene-Oligocene Transition in North America. Cambridge University Press, Cambridge.
• Clark, John (1970-03-27). "Population dynamics of Leptomeryx". Fieldiana Geology. 16 (16): 411–451. Retrieved 2014-04-20.