Where: Rosebud County, Montana (46.7° N, 107.8° W: paleocoordinates 53.4° N, 74.4° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Bearpaw Shale Formation (Montana Group), Late/Upper Campanian (83.5 - 70.6 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified, concretionary shale

Size class: macrofossils

Collected by C.T. Moore, W.A. Cobban in 1949; reposited in the USNM

Primary reference: W. A. Cobban. 1987. The Upper Cretaceous ammonite Rhaeboceras Meek in the western interior of the United States. United States Geological Survey Professional Paper 1477:1-15 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 175762: authorized by Matthew Clapham, entered by Matthew Clapham on 09.01.2016

Creative Commons license: CC BY (attribution)