Black Hank's Canyon (Oligocene of the United States)

Also known as UNSM Mo-109

Where: Morrill County, Nebraska (41.7° N, 103.1° W: paleocoordinates 42.5° N, 96.6° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Unit D Member (Gering Formation), Geringian (30.8 - 26.3 Ma)

• apparently the only locality in this unit apart from the "Megasespia" locality (see Gering C); based on Tedford et al. 1996, C and D are coeval facies

•Scotts Bluff National Monument section appears to fall entirely in Gering D based on Swisher 1982, Loope 1986, and Tedford et al. 1987; therefore, KA 985 dated at 25.6 (= 26.27) Ma by Evernden et al. 1964 (KA on volcanic ash) falls in this unit; date rejected by Tedford et al. 1996 on reasonable paleomagnetic grounds

•see stratigraphic range chart in Swisher 1982

• bed-level stratigraphic resolution

Environment/lithology: terrestrial; lithology not reported

Size classes: macrofossils, mesofossils

Reposited in the UNSM

Primary reference: R. H. Tedford, C. C. Swisher, D. R. Prothero, S. A. King, and T. E. Tierney. 1996. The Whitneyan-Arikareean transition in the High Plains. In D. R. Prothero, R. J. Emry (eds.), The Terrestrial Eocene-Oligocene Transition in North America 312-334 [J. Alroy/J. Alroy/M. Uhen]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 17474: authorized by John Alroy, entered by John Alroy on 15.05.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Artiodactyla - Leptomerycidae
Leptomeryx sp. Leidy 1853 ruminant
 Artiodactyla - Merycoidodontidae
"Megasespia middleswarti" = Sespia ultima2, "Mesoreodon megalodon" = Desmatochoerus megalodon1
"Megasespia middleswarti" = Sespia ultima2 Schultz and Falkenbach 1968 oreodont
"Black Hank's Canyon" UNSM Mo-109; upper Gering
"Mesoreodon megalodon" = Desmatochoerus megalodon1 Peterson 1907 oreodont
"Black Hank Canyon"; Mesoreodon does not range above Gering B according to Swisher 1982, but no Gering A or B collections are listed in this section
 Carnivora - Nimravidae
Nimravus brachyops3 Cope 1878 false sabre-tooth
 Carnivora - Canidae
Cormocyon copei Wang and Tedford 1992 bone-crushing dog