Ptychodus whipplei Marcou, 1858

Remarks

• Collector:    Keith Minor
• Formation:  Eagle Ford Group, Kamp Ranch Limestone
• Location:     Dallas County, TX

General Info

Synonyms (older names and misidentifications in the literature)

• extinct shell–crushing shark
• 1858 Ptychodus whipplei Marcou
• 1873 Ptychodus whipplei Marcou; Leidy
• 1876 Ptychodus whipplei Marcou; Newberry
• 1889 Ptychodus whipplei Marcou; Woodward
• 1890 Ptychodus whipplei Marcou; Williston
• 1907 Ptychodus cf. P. whipplei Marcou; Aguilera
• 1948 Ptychodus cf. P. whipplei Marcou; Maldonado-Koerdell
• 1973 Ptychodus whipplei Marcou; Cappetta
• 1976 Ptychodus whipplei Marcou; Edwards
• 1979 Ptychodus whipplei Marcou; Evetts
• 1985 Ptychodus whipplei Marcou; Wolberg
• 1989 Ptychodus whipplei Marcou; Finsley
• 1993 Ptychodus whipplei Marcou; Welton & Farish
• 1993 Ptychodus whipplei Marcou; Williamson, Kirkland, and Lucas

Stratigraphic Occurrence

• Mancos Formation, Middle Shale Member of Northeastern Arizona
• Mancos Formation, Lower Shale Member of Northeastern Arizona
• Mancos Formation of New Mexico
• Benton Group, Carlile Shale of South Dakota and Colorado
• Basal Austin Group, Atco Formation of North Texas
• Upper Eagle Ford Group, Arcadia Park Formation of North Texas
• Turonian Rocks of Northern Mexico (probably San Felipe Formation)

Age

• Ptychodus whipplei Marcou ranges from about the Collignoniceras woollgari (Mantell) zone to roughly the Peroniceras (Peroniceras) westphalicum (Schlüter) zone, from middle Turonian to middle Coniacian time (~92–88 mya).

Geographic Occurrence (not an all-inclusive list)

• Coahuila, Mexico
• Coconino County, AZ
• Pueblo County, Colorado
• Dallas County, TX
• Ellis County, TX
• Fall River County, SD
• Kansas
• Navajo County, AZ
• Nebraska
• New Mexico (no county given)
• San Miguel County, NM

Remarks

         For identification and descriptions, see:

• Cappetta, H.  1973.  Selachians from the Carlile Shale (Turonian) of South Dakota.  Journal  of  Paleontology  47 (3), 504-514.

• Welton, B. J; Farish, R. F.  1993.  The  Collector’s  Guide  to  Fossil  Sharks  and  Rays  from  the  Cretaceous  of  Texas.  Lewisville:  Before Time.

• Williamson, T. E.; Kirkland, J. I.; Lucas, S. G.  1993.  Selachians from the Greenhorn Cyclothem ("Middle" Cretaceous:  Cenomanian-Turonian), Black Mesa, Arizona, and the Paleogeographic Distribution of Late Cretaceous Selachians.  Journal  of  Paleontology  67 (3), 447-474.