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Acanthoceras amphibolum

Geological Range

Acanthoceras amphibolum Zone: Middle Cenomanian 94.96 ± 0.50

Paleogeographic Distribution

Texas, New Mexico, Kansas, Colorado, Wyoming, South Dakota, Montana, Japan, and Nigeria (source: Kennedy and Cobban, 1990a).

Remarks

Original presentation: Acanthoceras? amphibolum

Original publication: Morrow, A. L. 1935. Cephalopods from the Upper Cretaceous of Kansas. Journal of Paleontology 9(6): 463-473 [pp. 470, 472, 473; pl. 49, figs 1-4, 6, pl. 51, figs 3, 4, text fig. 4].

Syntypes: KUMIP 286264.

Type locality: “south bank of Smoky Hill River south of Wilson, Ellsworth County, Kansas” (Morrow, 1935, p. 473).

Type horizon: “upper Graneros shale” (Morrow, 1935, p. 473).

Other specimens: USNM 420216-420221.

PaleoDB taxon number: 299030.

Synonyms: Acanthoceras alvaradoense Moreman, 1942 (source: Kennedy and Cobban, 1990a); Acanthoceras hazzardi Stephenson, 1953 (source: Kennedy and Cobban, 1990a).

References: Cobban and Scott (1973), Cobban (1984), Kennedy and Cobban (1990a).

Origin of name: “Greek, amphibolus, doubtful; for the assignment doubtfully to Acanthoceras” (Cobban et al., 2006, p. 30).

Stratigraphic Occurrences

Campanian
Graneros Shale (KS)
Cenomanian
Acanthoceras amphibolum zone (CO)
Acanthoceras amphibolum zone (KS)
Acanthoceras amphibolum zone (MT)
Acanthoceras amphibolum zone (NM)
Acanthoceras amphibolum zone (SD)
Acanthoceras amphibolum zone (TX)
Acanthoceras amphibolum zone (WY)
Belle Fourche Formation (WY)
Belle Fourche Formation (Metoicoceras mosbyense zone) (WY)
Boquillas Formation (NM)
Dakota Sandstone (NM)
Dakota Sandstone (Paguate Sandstone Member) (NM)
Frontier Formation (WY)
Graneros Shale (CO)
Graneros Shale (KS)
Lake Waco Formation (Bluebonnet Member) (TX)
Mancos Shale (NM)
<i>Acanthoceras amphibolum</i> from the Cenomanian to Turonian Graneros Shale Fm. of Ellsworth County, Kansas (KUMIP 282253).
Acanthoceras amphibolum from the Cenomanian to Turonian Graneros Shale Fm. of Ellsworth County, Kansas (KUMIP 282253).
Syntype specimens of <i>Acanthoceras amphibolum</i> from the collections of the KUMIP. Kennedy and Cobban (1990, text-fig. 11) characterized KUMIP 286263 as the
Syntype specimens of Acanthoceras amphibolum from the collections of the KUMIP. Kennedy and Cobban (1990, text-fig. 11) characterized KUMIP 286263 as the "holotype."
Suture patterns of <i>Acanthoceras amphibolum</i>. See original caption for additional details. Image modified from text-figs 6b and 6e in Kennedy and Cobban (1990a in <i>Palaeontology</i>), made available through Biodiversity Heritage Library via a CC BY-NC-SA 4.0 license.
Suture patterns of Acanthoceras amphibolum. See original caption for additional details. Image modified from text-figs 6b and 6e in Kennedy and Cobban (1990a in Palaeontology), made available through Biodiversity Heritage Library via a CC BY-NC-SA 4.0 license.
Whorl section of <i>Acanthoceras amphibolum</i>. See original caption for additional details. Image modified from text-fig 5b in Kennedy and Cobban (1990a in <i>Palaeontology</i>), made available through Biodiversity Heritage Library via a CC BY-NC-SA 4.0 license.
Whorl section of Acanthoceras amphibolum. See original caption for additional details. Image modified from text-fig 5b in Kennedy and Cobban (1990a in Palaeontology), made available through Biodiversity Heritage Library via a CC BY-NC-SA 4.0 license.
Specimens of <i>Acanthoceras amphibolum</i>, including the holotype of <i>Acanthoceras alvaradoense</i> Moreman, 1942. See original captions for additional details. Image modified from text-figs 12-14 in Kennedy and Cobban (1990a in <i>Palaeontology</i>), made available through Biodiversity Heritage Library via a CC BY-NC-SA 4.0 license.
Specimens of Acanthoceras amphibolum, including the holotype of Acanthoceras alvaradoense Moreman, 1942. See original captions for additional details. Image modified from text-figs 12-14 in Kennedy and Cobban (1990a in Palaeontology), made available through Biodiversity Heritage Library via a CC BY-NC-SA 4.0 license.
Stratigraphic position unknown
Stratigraphic position unknown