Pine Ridge Escarpment ( of the United States)

Also known as Eagle Crag; Squaw Butte

Where: Sioux County, Nebraska (42.4° N, 103.8° W: paleocoordinates 43.3° N, 98.8° W)

• coordinate based on political unit

When: Harrison Formation, Harrisonian (24.8 - 20.4 Ma)

Environment/lithology: terrestrial

Primary reference: R. H. Tedford, T. Galusha, M. F. Skinner, B. E. Taylor, R. W. Fields, J. R. Macdonald, J. M. Rensberger, S. D. Webb, and D. P. Whistler. 1987. Faunal succession and biochronology of the Arikareean through Hemphillian interval (late Oligocene through earliest Pliocene epochs) in North America. In M. O. Woodburne (ed.), Cenozoic Mammals of North America: Geochronology and Biostratigraphy 153-210 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 17819: authorized by John Alroy, entered by John Alroy on 18.02.1993

Creative Commons license: CC BY (attribution)

Taxonomic list

• some material from Wyoming may be included
formation-level composite list; some records may pertain to localities south of Pine Ridge sensu stricto (e.g., Zodiolestes)
Harrison Fm. dated at 21.3 (= 21.86) Ma by Evernden et al. 1964 (KA 481); seems unreliable based on K content and percent atmospheric Ar
"devil's corkscrews" occur no higher than this level but as far down as the Monroe Creek Fm.: Hunt 1985a
beaver material reported by Martin 1987 comes from KUVP locs. 26 (Ellicott), 31, 91 (Breuger Ranch), and 115
"Cyclopidius densa" Schlaikjer 1935b: "lower Harrison southwest of Chadron"; this is said to be "Lower Miocene" by Loomis 1925 and Schlaikjer's attribution is of uncertain significance

"Promerycochoerus sp." listed by Hunt 1985a for Eagle Crag, but omitted by Tedford et al. 1987
 Rodentia - Castoridae
Fossorcastor greeni n. sp.2, "Steneofiber fossor n. sp." = Fossorcastor fossor, "Steneofiber barbouri n. sp." = Pseudopalaeocastor barbouri, Capacikala sp., Euhapsis breugerorum n. sp.2, Euhapsis ellicottae n. sp.2
Fossorcastor greeni n. sp.2 Martin 1987 beaver
from KUVP Wyo-91 DUPLICATE REF 2414 or 2425 or 2439
"Steneofiber fossor n. sp." = Fossorcastor fossor Peterson 1905 beaver
"Steneofiber barbouri n. sp." = Pseudopalaeocastor barbouri Peterson 1905 beaver
Capacikala sp. Macdonald 1963 beaver
Euhapsis breugerorum n. sp.2 Martin 1987 beaver
from KUVP Neb-31 DUPLICATE REF 2414 or 2425 or 2439
Euhapsis ellicottae n. sp.2 Martin 1987 beaver
from KUVP Wy-115, Niobrara Co. WY according to Xu 1996 DUPLICATE REF 2414 or 2425 or 2439
 Perissodactyla - Chalicotheriidae
Moropus sp. Marsh 1877 chalicothere
at Eagle Crag
 Perissodactyla - Rhinocerotidae
Menoceras sp. Troxell 1921 rhinoceros
definitely at Eagle Crag: Hunt 1985a
Diceratherium sp. Marsh 1875 rhinoceros
 Perissodactyla - Equidae
Equidae indet.1 Gray 1821 horse
Anchitheriinae indet.1 Leidy 1869 anchitheriine horse
 Carnivora - Amphicyonidae
Daphoenodon sp. Peterson 1909 bear-dog
 Carnivora - Mustelidae
cf. Promartes sp. Riggs 1942 mustelid carnivore
said to "probably" be Promartes
Oligobunis sp. Cope 1881 mustelid carnivore
Zodiolestes sp. Riggs 1942 mustelid carnivore
 Carnivora - Canidae
Hesperocyoninae indet.1 Tedford 1978 canid
Leptocyon sp. Matthew 1918 canine
Cormocyon haydeni4 Wang et al. 1999 bone-crushing dog
"Ellicott Ranch, Steer Pasture"; may include "Nothocyon sp."
Phlaocyon sp. Matthew 1899 bone-crushing dog
 Ungulata - Merycoidodontidae
"Mesoreodon megalodon" = Desmatochoerus megalodon Peterson 1907 oreodont
Phenacocoelus sp. Peterson 1907 oreodont
suggested to include the type of P. typus by Schultz and Falkenbach 1947, 1950, but placed in the Monroe Creek sensu stricto by Hunt 1985a; status of additional "head of Squaw Creek" and "Squaw Butte" specimens of Peterson 1928 unclear
Merychyus sp. Leidy 1858 oreodont
described by Peterson 1907 and Thorpe 1937 as from the "Lower Harrison beds" of Squaw Butte; does not include the type of "Phenacocoelus munroensis" from the type Monroe Creek (see)
 Ungulata - Entelodontidae
Dinohyus sp. Peterson 1905 even-toed ungulate
 Ungulata - Camelidae
Stenomylus gracilis3 Peterson 1907 camel
"Lower Harrison beds on the Niobrara (Running Water) River, Sioux County"; this is confirmed as below "Cork Screw beds" by Frick and Taylor 1968
Oxydactylus sp. Peterson 1904 camel
 Ungulata - Protoceratidae
Syndyoceras sp. Barbour 1905 protoceratid