Harris Ranch Unit E Silt ( of the United States)

Also known as Blue Ash Channel

Where: Fall River County, South Dakota (43.2° N, 103.2° W: paleocoordinates 44.1° N, 97.3° W)

• coordinate based on political unit

When: Arikareean (30.8 - 20.4 Ma)

• member-level stratigraphic resolution

Environment/lithology: terrestrial

Primary reference: W. F. Simpson. 1985. Geology and paleontology of the Oligocene Harris Ranch Badlands, southwestern South Dakota. Dakoterra 2(2):303-333 [J. Alroy/J. Alroy/J. Marcot]more details

PaleoDB collection 17520: authorized by John Alroy, entered by John Alroy on 18.02.1993, edited by Jonathan Marcot

Creative Commons license: CC BY (attribution)

Taxonomic list

• channel cuts into Brule Fm.; siltstone overlies basal microconglomerate
no evidence of reworking
Mammalia
 Rodentia - Aplodontidae
Ansomys cyanotephrus n. sp.3 Korth 2007 mountain beaver
 Rodentia - Sciuridae
Hesperopetes blacki n. sp.2 Emry and Korth 2007 squirrel
Hesperopetes jamesi n. sp.2 Emry and Korth 2007 squirrel
 Rodentia - Castoridae
Castoridae indet. Gray 1821 beaver
 Perissodactyla - Rhinocerotidae
Rhinocerotidae indet. Gray 1821 rhinoceros
Woodoceras brachyops n. gen. n. sp.4 Prothero 2005 rhinoceros
Diceratherium armatum Marsh 1875 rhinoceros
Diceratherium annectens4 Marsh 1873 rhinoceros
"Early Arikareean, Harris Ranch, ?Sharps Formation, Fall River County, South Dakota"
 Perissodactyla - Equidae
Miohippus cf. obliquidens1 Osborn 1904 anchitheriine horse
 Ungulata - Merycoidodontidae
Leptauchenia major1 Leidy 1856 oreodont
? Merycoidodon sp. Leidy 1848 oreodont
large: probably OK
 Ungulata - Entelodontidae
Entelodontidae indet. Lydekker 1883 even-toed ungulate
 Ungulata - Agriochoeridae
Agriochoeridae indet. Leidy 1869 agriochoerid
 Ungulata - Anthracotheriidae
Elomeryx cf. garbanii Macdonald 1970 anthracothere
 Ungulata - Protoceratidae
Protoceras skinneri n. sp. Patton and Taylor 1973 protoceratid
from "4 feet above a blue ash": see Patton and Taylor 1973