Bear Creek (Middle Titanotherium Beds) (Eocene of the United States)

Where: Shannon County, South Dakota (43.9° N, 102.6° W: paleocoordinates 45.2° N, 93.7° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Chadron Formation, Chadronian (37.2 - 33.9 Ma)

• member-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; siliciclastic sediments

Size class: macrofossils

Collected by T. C. Brown, F. B. Loomis in 1903

• Amherst College collection

Primary reference: R. S. Lull. 1905. Megacerops tyleri, a new species of titanothere from the Bad Lands of South Dakota. Journal of Geology 13(5):443-456 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 16900: authorized by John Alroy, entered by John Alroy on 15.05.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

• relationship of unit to members of Clark and Beerbower 1967 unclear
Reptilia
 Testudines - Pangeoemydidae
"Chrysemys inornata n. sp." = Echmatemys lativertebralis
"Chrysemys inornata n. sp." = Echmatemys lativertebralis Cope 1877 turtle
"at the head of Bear Creek in Spring Draw Basin" underneath a "titanotherium skeleton" (possibly the Brontops specimen)
Mammalia
 Perissodactyla - Brontotheriidae
"Megacerops tyleri n. sp." = Brontops tyleri
"Megacerops tyleri n. sp." = Brontops tyleri Lull 1905 brontothere
from "head of Bear Creek ... 35 feet above the base" of a 200 ft Chadron section; see Mader 1989