Cretodus crassidens (Dixon, 1850)

Remarks

• We would like to thank Ed and Cathy Swiatovy for allowing us to show this Cretodus tooth (> 2" from root to tip!).  Strat and locale:  Eagle Ford Group, Turonian (probably Arcadia Park Shale), Grayson County, TX.

General Info

Synonyms (older names and misidentifications in the literature)

• Extinct cousin of the Mackerel Shark
• 1850 Lamna crassidens Dixon; author?
• 1873 Otodus divaricatus Leidy; author?
• 1989 Leptostyrax crassidens (Dixon); Finsley
• 1993 Cretodus crassidens (Dixon); Welton and Farish

Stratigraphic Occurrence

• Upper Eagle Ford Group, Kamp Ranch Member of the Arcadia Park Formation of North Texas

• Basal Austin Group, Basal Atco Formation of Central Texas

• Upper Cretaceous (Formation) of Great Britain

Age

• Cretodus crassidens (Dixon) ranges from about the Collignoniceras woollgari (Mantell) zone to the Peroniceras haasi Young zone, lower Middle Turonian Stage to the lowermost Coniacian Stage (~92–88 mya).

Geographic Occurrence (not an all-inclusive list)

• Dallas County, TX

• Grayson County, TX

• Travis County, TX

Remarks

        For identification and descriptions, see:

• Finsley, C. 1989. A Field Guide to Fossils of Texas. Austin: Texas Monthly Press.
• Welton, B. J; Farish, R. F. 1993. The Collector’s Guide to Fossil Sharks and Rays from the Cretaceous of Texas. Lewisville: Before Time.