Where: Clark County, Arkansas (34.0° N, 93.4° W: paleocoordinates 38.0° N, 65.0° W)
• coordinate based on nearby landmark
• small collection-level geographic resolution
When: Nostoceras hyatti ammonoid zone, Saratoga Chalk Formation, Late/Upper Campanian (83.5 - 70.6 Ma)
• Was early Maastrichtian, updated by Kennedy and Cobban to late Campanian
• bed-level stratigraphic resolution
Environment/lithology: chalk
Size class: macrofossils
Collected by L.W. Stephenson, C.H. Dane; 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 197643: authorized by Matthew Clapham, entered by Matthew Clapham on 19.11.2018
Creative Commons license: CC BY (attribution)
Taxonomic list
Echinoidea | |
Hemiaster wetherbyi de Loriol 1887 heart urchin |