Elk Creek (100 m) (Eocene of the United States)

Also known as YPM 90b, 90c, 119, 120, 201, 202, 203, 204, 205

Where: Big Horn County, Wyoming (44.5° N, 108.0° W: paleocoordinates 49.2° N, 90.8° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Willwood Formation, Wasatchian (55.8 - 50.3 Ma)

Environment/lithology: terrestrial

Primary reference: D. M. Schankler. 1980. University of Michigan Papers on Paleontology 24 [J. Alroy/J. Alroy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 15507: authorized by John Alroy, entered by John Alroy on 18.02.1993

Creative Commons license: CC BY (attribution)

Taxonomic list

• all of the YPM localities are in Big Horn County
Mammalia
 Cimolesta - Coryphodontidae
Coryphodon sp. Owen 1845 pantodont
"2"
Coryphodon sp. Owen 1845 pantodont
"1"
 Cimolesta - Esthonychidae
Esthonyx spatularius Cope 1880 tillodont
 Cimolesta -
"Esthonyx grangeri" = Azygonyx grangeri
"Esthonyx grangeri" = Azygonyx grangeri Simpson 1937 tillodont
 Cimolesta - Pantolestidae
Palaeosinopa veterrima Matthew 1901 eutherian
 Leptictida - Leptictidae
Prodiacodon tauricinerei Jepsen 1930 eutherian
 Primates - Microsyopidae
Microsyopidae indet.1 Osborn and Wortman 1892 primate
 Primates - Omomyidae
Tetonius sp.1 Matthew 1915 tarsier
Teilhardina sp.2 Simpson 1940 tarsier
 Primates - Notharctidae
Cantius sp.1 Simons 1962 primate
 Primates - Paromomyidae
Phenacolemurinae indet.1 Simpson 1955 primate
Phenacolemur simonsi Bown and Rose 1976 primate
Ignacius graybullianus Bown and Rose 1976 primate
 Rodentia - Sciuravidae
cf. Knightomys depressus Loomis 1907 rodent
cf. Knightomys minor1 Wood 1965 rodent
 Rodentia - Ischyromyidae
Paramys cf. excavatus Loomis 1907 rodent
Paramys cf. copei Loomis 1907 rodent
 Condylarthra - Hyopsodontidae
Hyopsodus sp. Leidy 1870 condylarth
"loomisi/minor"
 Tribosphenida - Phenacodontidae
Ectocion osbornianus Cope 1882 condylarth
Copecion brachypternus1 Cope 1882 condylarth
Phenacodus sp.1 Cope 1873 condylarth
Phenacodus intermedius Granger 1915 condylarth
Phenacodus vortmani Cope 1880 condylarth
 Perissodactyla - Equidae
"Hyracotherium grangeri" = Sifrhippus grangeri
"Hyracotherium grangeri" = Sifrhippus grangeri Gingerich 1989 horse
"H. sp. 1"
 Creodonta - Oxyaenidae
Oxyaena gulo Matthew and Granger 1915 creodont
listed also by Gunnell and Gingerich 1991
 Ferae - Viverravidae
Didymictis leptomylus Cope 1880 placental
Viverravus sp. Marsh 1872 placental
"V. acutus/gracilis"
Viverravus sp. Marsh 1872 placental
"2"
 Ferae -
Uintacyon massetericus Cope 1882 placental
 Macroscelidea - Apheliscidae
Haplomylus speirianus Cope 1880 elephant shrew
Apheliscus sp. Cope 1875 elephant shrew
"wapitiensis/insidiosus"
 Tribosphenida - Arctocyonidae
Thryptacodon antiquus Matthew and Granger 1915 condylarth
Chriacus gallinae Matthew and Granger 1915 condylarth
 Acreodi - Mesonychidae
Pachyaena ossifraga Cope 1874 condylarth
 Hyaenodonta - Hyaenodontidae
Prototomus sp. Cope 1874 eutherian
"1"
Arfia sp.1 Van Valen 1965 eutherian
Prolimnocyon atavus Matthew and Granger 1915 eutherian
Didelphodus absarokae Cope 1881 eutherian
 Artiodactyla - Diacodexeidae
Diacodexis sp.1 Cope 1882 even-toed ungulate
 Multituberculata -
Neoliotomus ultimus Granger and Simpson 1928 multituberculate
described by Krause 1982 from YPM 90b and 119