Where: Yankton County, South Dakota (43.0° N, 97.3° W: paleocoordinates 44.6° N, 61.7° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Smoky Hill Chalk Member (Niobrara Formation), Coniacian to Coniacian (89.8 - 83.6 Ma)

• "approximately 15 feet below the contact of the Niobrara and the basal beds of the overlying Pierre formation."

• bed-level stratigraphic resolution

Environment/lithology: calcareous chalk

Size class: macrofossils

Collected by R. Martin in 3, 1957

• Found both in talus and in situ

Primary reference: W. Sevon. 1957. A Niobrara mosasaur from South Dakota. Proceedings of the South Dakota Academy of Science 36:144-146 [M. Carrano/H. Street]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 107782: authorized by Matthew Carrano, entered by Hallie Street on 15.04.2011

Creative Commons license: CC BY (attribution)