Where: Chihuahua, Mexico (29.5° N, 105.0° W: paleocoordinates 31.8° N, 73.1° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Boquillas Formation, Middle Turonian (93.5 - 89.3 Ma)

• Collignoniceras woollgari zone and Prionocyclus hyatti zone

• group of beds-level stratigraphic resolution

Environment/lithology: marine

Size class: macrofossils

Preservation: mold/impression

Reposited in the TMM

• '... observations are based on collections in the U.s. Geological survey at the Federal Center, Denver, Colorado, as well as material noted by King & Adkins (1946) and Powell (1963) plus additional material collected by Professor J. M. Hancock and ourselves from Powell's Cannonball Hill locality...'

Primary reference: W. J. Kennedy and W. A. Cobban. 1988. Mid-Turonian ammonite faunas from northern Mexico. Geological Magazine 125(6):593-612 [M. Aberhan/S. Nurnberg/S. Nurnberg]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 38966: authorized by Martin Aberhan, entered by Sabine Nürnberg on 18.05.2004

Creative Commons license: CC BY (attribution)