Leptomeryx

Leptomeryx Temporal range: middle Eocene to early Miocene[1]
Skeleton, Paleontology Museum of Zurich
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
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.

Taxonomy

Mounted skeleton

L. evansi

Leptomeryx was named by Leidy (1853). Its type is Leptomeryx evansi. It was assigned to Leptomerycinae by Matthew (1908); to Hypertragulidae by Cook (1934); and to Leptomerycidae by Leidy (1853) and then by Carroll (1988).^[3]

Morphology

Leptomeryx was a small deer-like ruminant with somewhat slender body.

Body mass

Four specimens were examined by Legendre and Roth for body mass.^[4]

• Specimen 1 weighed an estimated: 7.62 kg (17 lb)
• Specimen 2: 14.7 kg (32 lb)
• Specimen 3: 6.24 kg (14 lb)
• Specimen 4: 5.72 kg (13 lb)

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.^[5]
• Medicine Pole Hills, Bowman County, North Dakota (L. yoderi) ~38—33.9 Ma.^[6]

References

1. Webb, 1998, p. 474.
2. Webb, 1998, p.471.
3. R. L. Carroll. 1988. Vertebrate Paleontology and Evolution. W. H. Freeman and Company, New York 1-698
4. S. Legendre and C. Roth. 1988. Correlation of carnassial tooth size and body weight in recent carnivores (Mammalia). Historical Biology 1(1):85-98
5. Paleobiology database: Toadstool Park collection
6. Paleobiology database: Medicine Pole Hills collection

• 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.