Cynarctoides acridens

Cynarctoides acridens is an extinct species of Cynarctoides, belonging to the subfamily Borophaginae and tribe Phlaocyonini, a canine which inhabited most of west central North America from the Miocene epoch (Harrisonian stage to Early Barstovian stages) living 24.8—13.6 mya and existed for approximately 15.6 million years.

Description

Borophaginae were short-face, heavy-jawed canines. Cynarctoides acridens shared part of its period with a variety of bear dogs like Aelurodontina, Tomarctus and the giant mustelid genus of bone-crushing canidae.

Origin

Cynarctoides acridens is synonymous with Cynarctus mustelinus and was named by E. H. Barbour and H. J. Cook in 1914.^[1] Its discovery was in a Harrisonian terrestrial horizon in the Upper Harrison Beds Formation of Nebraska. Cynarctoides acridens was recombined as Notharctus acridens by William Diller Matthew in 1932. Under subsequent study, it was recombined as Cynarctoides acridens by P. O. McGrew in 1938 followed by Galbreath in 1956, J. Munthe in 1988, and Xiaoming Wang in 1999.

Morphology

Two specimens were examined by Legendre and Roth for body mass.^[2]

• Specimen 1 was estimated to weigh 1.42 kg (3.1 lb).
• Specimen 2 was estimated to weigh 1.48 kg (3.3 lb).

Fossil distribution

• Hidalgo Bluff Site, Oakville Formation, Washington County, Texas ~23.0—5.3 Ma.
• Nambe Site, Tesuque Formation, Santa Fe County, New Mexico ~23.0—5.3 Ma.
• Split Rock, Arikaree Formation, Natrona County, Wyoming, ~20.6—16.3 Ma.
• Yermo Site, Barstow Formation, San Bernardino County, California ~16.3—13.6 Ma.

References

• Martin, L.D. 1989. Fossil history of the terrestrial carnivora. Pages 536 - 568 in J.L. Gittleman, editor. Carnivore Behavior, Ecology, and Evolution, Vol. 1. Comstock Publishing Associates: Ithaca.
• - Bio One Data Base - Cynarctoides acridens
• Phylogentic Systematic of the Borophanginae, X. Wang, 1999