Chione (Chione) Craspedonia Dall in the Crystal River Formation (Eocene) in Peninsular Florida

Abstract

The youngest beds of the Crystal River Formation in peninsular Florida are generally considered to be late Eocene in age. The presence of the following genera and subgenera: Asterocyclina, Hantkenina, Cribrogloborotalia, Pseudophragmina (Proporocyclina), among the foraminiferids; the annelid worm Rotularia; the echinoid genera Wythella, Weisbordella, Eurhodia, Phymosoma; clearly indicate an Eocene age for these strata (Nicol, et al. , 1976, p. 143). The beds are referred the Rotularia vernoni zone (Nicol and Jones, 1982) and are equivalent to Puri's Asterocyclina-Spirolaea [sic] vernoni faunizone. It has been suggested by Druid Wilson (personal communication) that these beds may be reworked Oligocene strata; however, in the vicinity of Gainesville, Florida, there is no indication that the beds have been reworked. Isolated silicified boulders of Suwannee Limestone represent the only Oligocene material near Gainesville, and the sole Oligocene fossil that has withstood long erosion and reworking is the robust irregular echinoid Rhyncholampas gouldii (Williams, et al., 1977).