Twin Rivers of Washington (Oligocene of the United States)

Where: Washington (48.1° N, 122.8° W: paleocoordinates 47.8° N, 113.8° W)

• coordinate based on nearby landmark

When: Twin Rivers Formation, Late/Upper Oligocene (28.4 - 23.0 Ma)

Environment/lithology: marine; lithified shale

Primary reference: N. M. Tegland. 1931. The gastropod genus Galeodea in the Oligocene of Washington. University of California Publications in Geological Sciences 19(18):397-434 [P. Wagner/K. Koverman/K. Koverman]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 40737: authorized by Pete Wagner, entered by Kimberly Koverman on 28.06.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Gastropoda
 Tonnoidea - Cassidae