A new curved baculite from the Upper Cretaceous of Wyoming

W. A. Cobban

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USGS · 70156452

A new curved baculite from the Upper Cretaceous of Wyoming

W. A. Cobban

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Abstract

Baculites reduncus , n. sp., is a moderately large ammonite that has a curved shell, a large angle of taper, and a stout ovate cross section. Conspicuous broad, arcuate ribs cross the upper two-thirds of the flank. The suture, which is fairly complex, has a distinctive lateral lobe. All the types are from the lower part of the Rock River Formation near Rock River, Wyo. The species is of late Campanian age and marks a zone between the Zones of Baculites gregoryensis Cobban and B. scotti Cobban

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Journal of Research of the U.S. Geological Survey Article

Source-reported bounding extent: 39.8928799002948° to 41.86956082699455° latitude; -106.270751953125° to -104.2767333984375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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W. A. Cobban. 1977. A new curved baculite from the Upper Cretaceous of Wyoming. https://pubs.usgs.gov/publication/70156452

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