USGS 13408, Washington (Cretaceous of the United States)

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
 Spatangoida - Hemiasteridae
Hemiaster wetherbyi de Loriol 1887 heart urchin
 Spatangoida - Micrasteridae
Micraster americanus Stephenson 1941 heart urchin