Description: Mako shark (Isurus desori) upper lateral tooth (lingual view). The anterior teeth are much longer, more slender and robust. Roots of the upper teeth form a much more oblique angle than the lower teeth. I. desori is believed to be the ancestor of the extant I. retroflexus and some consider the differences too insignificant to be a separate species. I. desori is differentiated from I. hastalis in that the basal groove on I. desori is narrow and uniform. Mako teeth, with a few exceptions, have no serrations and no noticeable nutrient groove.

Age: Miocene-Pliocene.

Found By: Ed DeRouin.

Location Found: Peace River near Wauchula, FL.

Current Custodian: Ed DeRouin.

Identified By: Ed DeRouin.

References: Fossil Sharks of the Chespeake Bay Region, pp. 57-61.