Description of two species of Hoploscaphites (Ammonoidea, Ancyloceratina) from the Upper Cretaceous (Lower Maastrichtian) of the U.S. Western Interior

Title Variants

Alternative: Two species of Hoploscaphites

Related Titles

Series: Bulletin of the American Museum of Natural History, number 427

By

Landman, Neil H. , author

Kennedy, W. J. (William James) , author
Larson, Neal L. , author
Grier, Joyce C. , author
Grier, James W. , author
Linn, Tom. , author

Type

Book

Material

Published material

Publication info

New York, NY, American Museum of Natural History, [2019]

Notes

"Issued February 22, 2019."

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Two species of scaphitid ammonites (Ammonoidea: Ancyloceratina) from the Upper Cretaceous (lower Maastrichtian) of the Western Interior of North America are described. Hoploscaphites macer, n. sp., is medium size, with coarse ribs on the phragmocone, which become finer on the body chamber, and closely spaced ventrolateral tubercles. It occurs in the upper part of the Baculites baculus Zone and lower part of the overlying B. grandis Zone in the Pierre Shale in Montana, Wyoming, and Colorado, and in the Bearpaw Shale in Montana. Hoploscaphites criptonodosus (Riccardi, 1983) is larger and more coarsely ornamented, including one or two rows of lateral tubercles on the flanks of the phragmocone. It occurs in the upper part of the Baculites baculus Zone and overlying B. grandis Zone in the Pierre Shale in Montana, Wyoming, Colorado, and possibly South Dakota, and in the Bearpaw Shale in Montana and Saskatchewan, Canada. Both species form part of an evolving lineage of Hoploscaphites that first appears in the Western Interior of North America in the middle Campanian.

Subjects

Ammonoidea , Bearpaw Formation , Cretaceous , Great Plains , Hoploscaphites criptonodosus , Hoploscaphites macer , Mollusks, Fossil , Paleontology , Pierre Shale , Saskatchewan , West (U.S.)

Call Number

QH1 .A4 no.427 2019

Language

English

Identifiers

DOI: https://doi.org/10.1206/0003-0090.427.1.1
OCLC: 1087505935