Antelope Creek (SDSM V-582) (Eocene of the United States)

Where: Harding County, South Dakota (45.6° N, 103.9° W: paleocoordinates 47.3° N, 93.9° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Slim Buttes Formation, Duchesnean (40.4 - 37.2 Ma)

Environment/lithology: fluvial; siliciclastic sediments

• fauna "suggests that a permanently flowing river was present"
• the formation "is a thin sequence of variegated sands, silts, and clays"

Size class: macrofossils

Collected by B. White, J. Clark in 1958; reposited in the SDSM

Primary reference: P. R. Bjork. 1967. Latest Eocene vertebrates from northwestern South Dakota. Journal of Paleontology 41(1):227-236 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 16823: authorized by John Alroy, entered by John Alroy on 12.04.1997

Creative Commons license: CC BY (attribution)

Taxonomic list

Actinopteri
 Lepisosteiformes - Lepisosteidae
Lepisosteus sp. Agassiz 1843 gar
Reptilia
 Testudines - Trionychidae
Trionychidae indet. Gray 1825 softshell turtle
 Testudines - Panemydidae
Pseudograptemys sp.2 Hutchison 1996 turtle
compared to G. inornata and G. cordifera
 Crocodylia - Alligatoridae
"Allognathosuchus cf. riggsi" = Alligator prenasalis
"Allognathosuchus cf. riggsi" = Alligator prenasalis Loomis 1904 alligator
jaw fragment
Mammalia
 Perissodactyla - Brontotheriidae
Duchesneodus uintensis1 Peterson 1931 brontothere
 Perissodactyla - Amynodontidae
Amynodontopsis bodei Stock 1933 odd-toed ungulate
 Perissodactyla - Tapiridae
? Colodon cingulatus Douglass 1902 tapir
 Perissodactyla - Equidae
Duchesnehippus intermedius1 Peterson 1932 horse
 Ungulata - Agriochoeridae
Agriochoeridae indet. Leidy 1869 agriochoerid
 Ungulata - Protoceratidae