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Didymoceras stevensoni

Geological Range

Didymoceras stevensoni Zone: Upper Campanian 75.19 ± 0.28 to 75.08 ± 0.11

Paleogeographic Distribution

New Mexico to Montana

Stratigraphic Occurrences

Campanian
Bearpaw Shale (Upper) (MT) [Campanian]
Pierre Shale (CO)
Pierre Shale (NM)
Pierre Shale (SD) [Campanian]
Rock River Formation (WY)
Holotype of <i>Didymoceras stevensoni</i> (USNM 12307). Original unmodified images provided by courtesy of the Smithsonian NMNH and adapted and presented here under a Creative Commons BY-NC 4.0 license (NMNH GUID http://n2t.net/ark:/65665/3978659d0-4685-4bb0-8cbb-0a7206342474).
Holotype of Didymoceras stevensoni (USNM 12307). Original unmodified images provided by courtesy of the Smithsonian NMNH and adapted and presented here under a Creative Commons BY-NC 4.0 license (NMNH GUID http://n2t.net/ark:/65665/3978659d0-4685-4bb0-8cbb-0a7206342474).
<i> Didymoceras stevensoni </i> from the Pierre Shale Fm. of Niobrara County, Wyoming (YPM 86706).
Didymoceras stevensoni from the Pierre Shale Fm. of Niobrara County, Wyoming (YPM 86706).
Stratigraphic position unknown
Stratigraphic position unknown