Where: Phillips County, Montana (47.7° N, 107.8° W: paleocoordinates 54.4° N, 73.8° W)

• coordinate stated in text

• 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 shale

Size class: macrofossils

Collected by Howard Ehrle in 1986; 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 178324: authorized by Matthew Clapham, entered by Matthew Clapham on 30.04.2016

Creative Commons license: CC BY (attribution)