"Inoceramus" nebrascensis Owen, 1852

Remarks

• Collector:    Ralph Johnson (M.A.P.S. collection)
• Formation:  Montana Group, Pierre Shale (either DeGrey or Lower Unnamed Shale Member)
• Location:     South Dakota

General Info

Synonyms (older names and misidentifications in the literature)

• 1852 Inoceramus nebrascensis Owen

• 1867 Inoceramus sagensis var. nebrascensis Owen; Meek

• 1876 Inoceramus sagensis var. nebrascensis Owen; Meek & Hayden

• 1963 Does not = Inoceramus nebrascensis Owen; Tsagareli

• 1963 possibly = Inoceramus sagensis Owen; Tsagareli

• 1977 "Inoceramus" nebrascensis Kauffman

• 1978 Inoceramus pteroides pyrenaicus Sornay (in part)

• 1982 Does not = Inoceramus aff. pteroides pyrenaicus Sornay; Sornay

• 2001 "Inoceramus" nebrascensis Owen; Walaszczyk, Cobban & Harries

• 2004 "Inoceramus" nebrascensis Owen; Walaszczyk  

Stratigraphic Occurrence

• Montana Group, upper Pierre Formation of southwestern South Dakota

• Early Late Campanian rocks of Poland

• Early Late Campanian rocks of Spain

Age

• Inoceramus nebrascensis Owen ranges from about the Exiteloceras jenneyi Whitfield zone to about the Baculites compressus (?) zone, early Late Campanian Stage (~74–73 mya).

Geographic Occurrence

• Pennington County, SD

• Vistula River Valley, Poland

• Shannon County, SD

• Spain

Remarks

         For identification, descriptions, and ranges, see:

• Meek, F. B.  1876.  A Report on the Invertebrate Cretaceous and Tertiary Fossils of the Upper Missouri Country.  United States Geologic and Geographic Survey of the Territories (Hayden) 9, 52; Plate 13, fig's 2a and 2b.

• Walaszczyk, I.  2004.  Inoceramids and Inoceramid Biostratigraphy of the Upper Campanian to Basal Maastrichtian of the Middle Vistula River Section, Central Poland.  Acta Geologica Polonica 54, 151; text-fig's 38 and 39.