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Current Taxonomic Status of Late Cretaceous Ammonoid Species from the Western Interior Seaway Assigned to the Family Baculitidae (Ancyloceratina: Turrilitaceae)

Jonathan R. Hendricks

Paleontological Research Institution, Ithaca, New York

Note: Names in green are accepted; names in red are synonyms. Return to main list here. This page was last updated October 16, 2017.

Class Cephalopoda

Order Ammonoidea Zittel, 1884

Suborder Ancyloceratina Wiedmann, 1966

Duration: Lower Tithonian to Upper Maastrichtian (Source: Wright et al., 1996).

Superfamily Turrilitaceae Gill, 1871

Duration: Lower Albian to Upper Maastrichtian (Source: Wright et al., 1996).

Family Baculitidae Gill, 1871

Duration: Upper Albian to Upper Maastrichtian (Source: Wright et al., 1996).

Genus Baculites Lamarck, 1799

Type species: Baculites vertebralis Lamarck, 1801

Duration:  Upper Turonian to Upper Maastrichtian (Wright et al., 1996).

PaleoDB taxon number: 14603.

Baculites asper Meek, 1876Baculites asperiformis Meek, 1876

Reason for equivalency: junior synonym (see Cobban, 1962).

Baculites asperiformis Meek, 1876

Original presentation: Baculites asperiformis

Original publication: Meek. 1876. [p. 405, pl. 39, figs. 10a, d].

Lectotype: USNM 178a.

Type horizon: “Eagle and Claggett Formations” (Cobban, 1962, p. 711).

Type locality: Judith River, Montana (Cobban, 1962).

Other specimens: USNM 178b (paratype), USNM 131015a-f, USNM 13106a,b.

WIS occurrences:

Campanian: Pakowki Formation (Alberta) (Cobban, 1962).

Campanian: Claggett Shale (MT) (Cobban, 1962).

Campanian: Pierre Shale (Sharon Springs Member) (SD) (Cobban, 1962).

Campanian: Pierre Shale (Sharon Springs Member) (WY) (Cobban, 1962).

Campanian: Pierre Shale (lower part) (CO) (Cobban, 1962).

Campanian: Pierre Shale (lower part) (WY) (Cobban, 1962).

Campanian: Mancos Shale (CO) (Cobban, 1962).

Campanian: Steele Shale (WY) (Cobban, 1962).

Campanian: Cody Shale (WY) (Cobban, 1962).

Zonation: Baculites asperiformis Zone, Upper Campanian (Cobban et al., 2006).

PaleoDB taxon number: 130338.

Synonyms: Baculites asperoides Meek and Hayden, 1861 (nomen nudum, Cobban, 1962); Baculites asper Meek, 1876 (junior synonym, Cobban, 1962).

References: Cobban (1962), Cobban et al. (2006).

Origin of name: “Latin, asper, rough, forma, shape” (Cobban et al., 2006, p. 30).

Baculites asperoides Meek and Hayden, 1861Baculites asperiformis Meek, 1876

Reason for equivalency: nomen nudum (see Cobban, 1962).

Baculites baculus Meek and Hayden, 1861

Original presentation:

Original publication: Meek and Hayden. 1861.

Holotype: USNM 1916.

Type locality: “near Glenrock, Wyo.” (Gill and Cobban, 1973).

Type horizon: Fox Hills Sandstone (Gill and Cobban, 1973).

Other specimens:

WIS occurrences:

Maastrichtian: Fox Hills Sandstone (Gill and Cobban, 1973).

Other occurrences: “a migrant from the Gulf coastal area” (Gill and Cobban, 1973, p. 10).

PaleoDB taxon number: 130774.

References: Gill and Cobban (1973); Cobban et al. (2006).

Origin of name: “Latin, baculum, rod or staff” (Cobban et al., 2006, p. 30).

Remarks: This species … a migrant from the Gulf coastal area, is characterized by its large size, circular to broadly ovate section, broad arcuate flank ribs, and suture much like that of pre-gregoryensis baculites … . The holotype, from the Fox Hills Sandstone near Glenrock, Wyo., was illustrated by Meek (1876, text figs. 51, 52) .

Baculites clinolobatus Elias, 1933

Baculites columna Morton, 1834

Original presentation: Baculites columna

Original publication. Morton. 1834. [p. 44, pl. 19, fig. 8].

Syntypes: ANSP 72867 (5 specimens) (Cobban and Kennedy, 1992).

Type locality: Prairie Bluff, Alabama (Cobban and Kennedy, 1992).

Type horizon: Prairie Bluff Chalk (Cobban and Kennedy, 1992).

Other specimens: BHI 2035.

WIS occurrences:

Maastrichtian: Fox Hills Formation (Timber Lake Member) (SD) (Cobban and Kennedy, 1992).

Maastrichtian: Fox Hills Formation (Trail City Member) (SD) (Cobban and Kennedy, 1992).

Other occurrences: Prairie Bluff Chalk (AL) (Cobban and Kennedy, 1992); Prairie Bluff Chalk (MS) (Cobban and Kennedy, 1992); Corsicana Fm. (TX) (Cobban and Kennedy, 1992); “Maastrichtian of the San Joaquin Valley, California” (Cobban and Kennedy, 1992, p. 683).

Reference: Cobban and Kennedy (1992).

Baculites compressus Say, 1820

Original presentation: Baculites compressa

Original publication: Say. 1820. [p. 41].

Types: “Morton’s types were from the Pierre Shale near or at the Great Bend of the Missouri River below Fort Pierre, S. Dak.” (Cobban et al., 1992).

Other specimens: USNM 449794-449797.

WIS occurrences:

Campanian: Pierre Shale (CO) (Cobban et al., 1992).

Zonation: Baculites compressus Zone, Upper Campanian (73.52 +/- 0.39 Ma) (Cobban et al., 2006).

PaleoDB taxon number: 130325.

References: Cobban et al. (1992).

Diagnosis: “A moderately large species that has a compressed whorl section, smooth flanks in most growth stages, a smooth or weakly ribbed venter, and a complex suture characterized by the terminal branches of the lateral lobe being almost pinched off” (Cobban et al., 1992, p. A7).

Baculites cuneatus Cobban, 1962

Original presentation: Baculites cuneatus

Original publication: Cobban, W. A. 1962. New baculites from the Bearpaw Shale and equivalent rocks of the Western Interior. Journal of Paleontology 36(1): 126-135. [pp. 127-129, pl. 25, figs. 1-8, text-fig. 1b].

Holotype: USNM 108966.

Type locality: Big Horn County, Montana.

Type horizon: Bearpaw Shale.

Other specimens: USNM 108967a, USNM 131116.

WIS occurrences:

Campanian: Bearpaw Shale (MT) (Cobban, 1962).

Zonation: Baculites cuneatus Zone, Upper Campanian (Cobban et al., 2006).

PaleoDB taxon number: not in database.

References: Cobban (1962).

Diagnosis: “This species, which is large for the genus, is characterized by its trigonal cross section and very narrow venter. The juveniles are smooth, commonly curved, and have a high angle of taper. The adults are straight, have a low angle of taper, and possess moderately strong ventral and lateral ribbing. The suture is complex” (Cobban, 1962, p. 127).

Baculites eliasi Cobban, 1958

Baculites gilberti Cobban, 1962

Original presentation: Baculites gilberti

Original publication: Cobban. 1962. [p. 716-717, pl. 108, figs. 5-13, text-figs. 1d-f].

Holotype: USNM 108911.

Type locality: Boulder County, Colorado (Cobban, 1962).

Type horizon: Pierre Shale.

Other specimens: USNM 108912a-e.

WIS occurrences:

Campanian: Pierre Shale (CO) (Cobban, 1962).

Campanian: Mancos Shale (CO) (Cobban, 1962).

Campanian: Mancos Shale (Loyd Member) (CO) (Cobban, 1962).

PaleoDB taxon number: not in database.

Reference: Cobban (1962).

Origin of name: “named for G. K. Gilbert” (Cobban, 1962, p. 716).

Baculites grandis Hall and Meek, 1856

Baculites gregoryensis Cobban, 1951

Baculites jenseni Cobban, 1962

Original presentation: Baculites jenseni

Original publication: Cobban, W. A. 1962. New baculites from the Bearpaw Shale and equivalent rocks of the Western Interior. Journal of Paleontology 36(1): 126-135. [pp. 129-131, pl. 26, figs. 1-12, text-fig. 1a].

Holotype: USNM 131117.

Type locality: Rosebud County, Montana (Cobban, 1962).

Type horizon: Bearpaw Shale (Cobban, 1962).

Other specimens: USNM 13118a,b, USNM 13119a,b.

WIS occurrences:

Campanian: Bearpaw Shale (MT) (Cobban, 1962).

Campanian: Lewis Shale (WY) (Cobban, 1962).

Campanian: Pierre Shale (CO) (Cobban, 1962).

Campanian: Pierre Shale (Richard Sandstone Member) (CO) (Cobban, 1962).

Zonation: Baculites jenseni Zone, Upper Campanian (Cobban, 1962).

PaleoDB taxon number: not in database.

References: Cobban (1962).

Origin of name: “named for Dr. Fred S. Jensen” (Cobban, 1962, p. 129).

Diagnosis: “This species is larger than average size for the genus. It is characterized by its straightness, low degree of taper, stout ovate section, smooth flanks with ventro-lateral depression, and complex suture. Young adults have about 9 ventral ribs per shell diameter but on old adults the venter tends to become smooth” (Cobban, 1962, p. 129).

Baculites larsoni Cobban and Kennedy, 1992

Original presentation: Baculites larsoni

Original publication: Cobban, W. A. and W. J. Kennedy. 1992. The last western interior Baculites from the Fox Hills Formation of South Dakota. Journal of Paleontology 66(4): 682-684.

Holotype: USNM 450318

Type locality: Dewey County, South Dakota (Cobban and Kennedy, 1992).

Type horizon: Fox Hills Formation (Timber Lake Member) (Cobban and Kennedy, 1992).

Other specimens: USNM 450319, USNM 450320, USNM 450321, USNM 450322, BHI 2036.

WIS Occurrences:

Maastrichtian: Fox Hills Formation (Timber Lake Member) (SD) (Cobban and Kennedy, 1992).

PaleoDB taxon number: not in database.

Reference: Cobban and Kennedy (1992).

Origin of name: “[f]or Neal L. and Peter L. Larson of the Black Hills Institute of Geological Research” (Cobban and Kennedy, 1992, p. 682).

Baculites maclearni Landes, 1940

Original presentation: Baculites mclearni

Original publication. Landes. 1940. [p. 165, pl. 7, figs. 1-3].

Holotype: Geological Survey of Canada Collections 9366.

Type locality: Alberta (see details in Cobban and Kennedy, 1993).

Type horizon: Pakowki Formation (Cobban and Kennedy, 1993).

Other specimens: USNM 441188, USNM 441187, USSNM 441186, USNM 441184, USNM 441185, USNM 441182.

WIS occurrences:

Campanian: Baculites mclearni Zone (Alberta) (Cobban and Kennedy, 1993).

Campanian: Baculites mclearni Zone (Saskatchewan) (Cobban and Kennedy, 1993).

Campanian: Baculites mclearni Zone (WY) (Cobban and Kennedy, 1993).

Campanian: Baculites mclearni Zone (MT) (Cobban and Kennedy, 1993).

Campanian: Baculites mclearni Zone (CO) (Cobban and Kennedy, 1993).

Campanian: Baculites mclearni Zone (UT) (Cobban and Kennedy, 1993).

Campanian: Baculites mclearni Zone (NM) (Cobban and Kennedy, 1993).

Campanian: Baculites mclearni Zone (TX) (Cobban and Kennedy, 1993).

Campanian: Wolfe City Sand (TX) (Cobban and Kennedy, 1993).

Zonation: Baculites mclearni Zone, Upper Campanian (Cobban et al., 2006).

PaleoDB taxon number: 130341.

References: Cobban and Kennedy (1993); Cobban et al. (2006).

Origin of name: “[f]or Frank Harris McLearn (1885-1964)” (Cobban et al., 2006, p. 32).

Baculites obtusus Meek, 1876

Original presentation: Baculites anceps Lamarck var. obtusus

Original publication: Meek. 1876. [p. 406, text-figs. 57-60].

Lectotype: USNM 1934a.

Type locality: Converse County, Wyoming (see Cobban, 1962).

Type horizon:  probably the Steele Shale (see discussion in Cobban, 1962).

Other specimens: USNM 1934b (paratype), USNM 131011a-e, USNM 131012.

WIS occurrences:

Campanian: Pierre Shale (lower part) (SD) (Cobban, 1962).

Campanian: Pierre Shale (Sharon Springs Member) (CO) (Cobban, 1962).

Campanian: Pierre Shale (Sharon Springs Member) (SD) (Cobban, 1962).

Campanian: Cody Shale (upper part) (WY) (Cobban, 1962).

Campanian: Steele Shale (WY) (Cobban, 1962).

Campanian: Claggett Shale (lower part) (MT) (Cobban, 1962).

Campanian: Pakowki Shale (Alberta) (Cobban, 1962).

Zonation: Baculites obtusus Zone, Upper Campanian, 80.58 +/- 0.55 Ma (Cobban et al., 2006).

PaleoDB taxon number: 130336.

References: Cobban (1962), Cobban et al. (2006).

Baculites perplexus Cobban, 1962

Original presentation: Baculites perplexus

Original publication: Cobban, W. A. 1962. Baculites from the lower part of the Pierre Shale and equivalent rocks in the Western Interior. Journal of Paleontology 36(4): 704-718. [p. 714-716, pl. 107, figs. 1-16, text-figs 1a-c.]

Holotype: USNM 108914.

Type locality: “Mesozoic locality D255 near Glenrock, Wyoming” (Cobban, 1962, p. 714).

Type horizon: Steele Shale.

Other specimens: USNM 108915a-f.

WIS occurrences:

Campanian: Stelle Shale (WY) (Cobban, 1962).

Campanian: Pierre Shale (Mitten Member) (Cobban, 1962)

Campanian: Cody Shale (Claggett Member) (MT) (Cobban, 1962)

Campanian: Mancos Shale (CO) (Cobban, 1962)

Zonation: Baculites perplexus Zone.

PaleoDB taxon number: not in database.

Reference: Cobban (1962).

Baculites reduncus Cobban, 1977

Baculites rugosus Cobban, 1962

Original presentation: Baculites rugosus

Original publication: Cobban, W. A. 1962. New baculites from the Bearpaw Shale and equivalent rocks of the Western Interior. Journal of Paleontology 36(1): 126-135. [pp. 131-134, pl. 27, figs. 1-12, text-fig. 1a].

Holotype:

Diagnosis: “this large species is characterized by its very strongly ribbed venter and complex suture with expanded elements. Most specimens have a high degree of taper slender ovate section, broad venter, and, in the late adult growth stage, lateral ribs. Ventral ribs on adults are ordinarily spaced 3 or 4 for the shell diameter” (Cobban, 2006, p. 131).

Baculites reesidei Elias, 1933

Baculites scotti Cobban, 1958

Baculites undatus Stephenson, 1941

Original presentation: Baculites undatus

Original publication: Stephenson. 1941. [p. 405, pl. 79, figs. 5-10].

Holotype: USNM 77245.

Type locality: Navarro County, Texas (Cobban et al., 1992).

Type horizon: Nacatoch Sand (Cobban et al., 1992).

Other specimens: USNM 77246, USNM 77247.

WIS occurrences:

Campanian: Pierre Shale (CO) (Cobban et al., 1992).

PaleoDB taxon number: 131009.

Diagnosis: A moderately sized species that has a stout, subelliptical cross section; an ornament of strong, arcuate, nodelike ribs; and a fairly simple suture characterized by its rectangular, bifid lateral lobe. (Cobban et al., 1992, p. A7).

Baculites yokoyamai Tokunaga and Shimizu, 1926

Original presentation: Baculites (Lechitesyokoyamai

Original publication: Tokunaga and Shimizu. 1926. [p. 195, pl. 22, figs 5a, 5b, pl. 26, fig. 11].

Types: awaiting determination.

Type locality: awaiting determination.

Type horizon: awaiting determination.

Other specimens: USNM 328704-328706 (Cobban and Cook, 1983).

WIS occurrences:

Turonian: Mancos Shale (Rio Salado Tongue) (NM).

Other occurrences: awaiting determination.

PaleoDB taxon number: 143702.

Synonyms: Baculites besairiei Collignon, 1931 (source: Cobban and Hook, 1983).

References: Cobban and Cook (1983).

 Genus Sciponoceras Hyatt, 1894

Type species: Hamites baculoide Mantell, 1822

Duration: Upper Albian to Upper Turonian (Wright et al., 1996).