Powder River 51-20/21/22/23/24 (Eocene of the United States)

Where: Johnson County, Wyoming (44.0° N, 106.6° W: paleocoordinates 48.5° N, 89.4° W)

• coordinate based on political unit

When: "Wasatch" Formation, Wasatchian (55.8 - 50.3 Ma)

Environment/lithology: terrestrial

Primary reference: E. Delson. 1971. Fossil mammals of the early Wasatchian Powder River local fauna, Eocene of northeast. Bulletin of the American Museum of Natural History 146(4) [J. Alroy/J. Alroy/M. Uhen]more details

PaleoDB collection 16020: authorized by John Alroy, entered by John Alroy on 18.02.1993

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Primates - Microsyopidae
Arctodontomys wilsoni1 Szalay 1969 primate
 Cimolesta - Coryphodontidae
Coryphodon sp. Owen 1845 pantodont
 Lipotyphla - Erinaceidae
Erinaceidae indet.5 Fischer von Waldheim 1817 hedgehog
"possibly" Dartonius jepseni; includes "cf. 'Leptacodon' jepseni"; "Nyctitheriidae indet." of Bown and Schankler 1982
 Perissodactyla - Palaeotheriidae
Hyracotherium sp.1 Owen 1841 odd-toed ungulate
 Macroscelidea - Apheliscidae
Haplomylus speirianus Cope 1880 elephant shrew
Apheliscus sp.2 Cope 1875 elephant shrew
 Trogontia - Esthonychidae
Esthonyx spatularius3 Cope 1880 tillodont
 Ungulata - Hyopsodontidae
Hyopsodus sp.1 Leidy 1870 condylarth
 Ungulata - Diacodexeidae
Diacodexis primus4 Krishtalka and Stucky 1985 even-toed ungulate
 Ungulata - Phenacodontidae
Ectocion osbornianus Cope 1882 condylarth