Where: Clark County, Arkansas (34.1° N, 93.1° W: paleocoordinates 38.0° N, 64.7° W)
• coordinate based on nearby landmark
• small collection-level geographic resolution
When: Marlbrook Marl Formation, Late/Upper Campanian (83.5 - 70.6 Ma)
• bed-level stratigraphic resolution
Environment/lithology: marine; marl
Size class: macrofossils
Collected by L.W. Stephenson; reposited in the USNM
Primary reference: C. W. Cooke. 1953. American Upper Cretaceous Echinoidea. United States Geological Survey Professional Paper 254-A:1-44 [W. Kiessling/U. Merkel/M. Clapham]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 78183: authorized by Wolfgang Kiessling, entered by Uta Merkel on 30.01.2008
Creative Commons license: CC BY (attribution)
Taxonomic list
Echinoidea | |
Hemiaster wetherbyi de Loriol 1887 heart urchin | |
Micraster americanus Stephenson 1941 heart urchin |