Egila sp. cf. E. gordonae (Bartsch, 1955) Edna Gordon's Odostome Fossil

Scanning electron micrographs (SEM)

   The adult shell on the left and the sub-adult shell on the right demonstrates the heterostrophy so characteristic of the family Pyramidellidae (Subclass Heterobranchia).  Both were collected from the lower Pinecrest beds, Upper Tamiami Formation, Sarasota County, Florida. This exposure was deposited during the Lower Pliocene Epoch ~ 3,000,000 years ago. SEMs produced in collaboration with Dr. Ann Heatherington, Dept. Geological Sciences, University of Florida, Gainesville, FL. Note the uncanny conchological resemblance to Lirobarleeia gradata (d'Orbigny, 1842) (Prosobranchia: Rissoidae). Such convergent evolution of shell characters is termed homoplasy.