Where: Hempstead County, Arkansas (33.8° N, 93.7° W: paleocoordinates 37.9° N, 65.4° W)
• coordinate estimated from map
• 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: marine; chalk
Size class: macrofossils
Reposited in the USGS
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 78199: authorized by Wolfgang Kiessling, entered by Uta Merkel on 31.01.2008, edited by Matthew Clapham
Creative Commons license: CC BY (attribution)
Taxonomic list
Echinoidea | |
Hemiaster wetherbyi de Loriol 1887 heart urchin | |
Micraster americanus Stephenson 1941 heart urchin |