USGS Mesozoic D12236, St. Vrain River (Cretaceous of the United States)

Where: Weld County, Colorado (40.2° N, 105.0° W: paleocoordinates 46.8° N, 81.1° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Hoploscaphites birkelundae ammonoid zone, Milliken Sandstone Member (Fox Hills Sandstone Formation), Late/Upper Maastrichtian (70.6 - 66.0 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified sandstone

Size class: macrofossils

Reposited in the USNM

Primary reference: W. J. Kennedy, N. H. Landman, and W. A. Cobban. 1996. The Maastrichtian ammonites Coahuilites sheltoni Böse, 1928, and Sphenodiscus pleurisepta (Conrad, 1857), from the uppermost Pierre Shale and basal Fox Hills Formation of Colorado and Wyoming. American Museum Novitates 3186:1-14 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 178312: authorized by Matthew Clapham, entered by Matthew Clapham on 30.04.2016

Creative Commons license: CC BY (attribution)

Taxonomic list

Cephalopoda
 Ammonitida - Sphenodiscidae
Sphenodiscus pleurisepta Conrad 1857 ammonite