USGS M8699 (Cretaceous of the United States)

Where: Medina County, Texas (29.3° N, 99.1° W: paleocoordinates 34.9° N, 72.5° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Baculites maclearni ammonoid zone, Anacacho Limestone Formation, Middle Campanian (83.5 - 70.6 Ma)

• Swezey and Sullivan (2004) correlate this bed to the Baculites maclearni zone., which is middle Campanian in Gradstein et al., 2004.

• bed-level stratigraphic resolution

Environment/lithology: marine; limestone

• lithology described as a chalky skeletal limestone

Size class: mesofossils

Reposited in the USGS

Primary reference: W. P. Elder. 1996. Bivalves and Gastropods from the Middle Campanian Anacacho Limestone, south central Texas. Journal of Paleontology 70(2):247-271 [M. Patzkowsky/K. Layou/J. Alroy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 3610: authorized by Mark Patzkowsky, entered by Karen Layou on 05.08.1999

Creative Commons license: CC BY (attribution)

Taxonomic list

 Arcida - Cucullaeidae
Cucullaea sp. Lamarck 1801 clam
 Ostreida - Gryphaeidae
 Cardiida - Cardiidae
Echinoidea indet. Leske 1778 sea urchin