Middle and Upper Silurian chitinozoan succession in Florida subsurface

Unmetamorphosed Paleozoic rocks are present in the subsurface of Florida. Silurian acritarchs, chitinozoans, and miospores have been recovered from black to gray shales of four wells in the north-central portion of the state. On account of its palynomorphs, mainly chitinozoans, this material is dated as very latest upper Llandoverian through upper Ludlovian or very basal Gedinnian. The Florida ranges of twenty-eight stratigraphically valuable chitinozoan taxa are plotted; nearly all taxa are illustrated by photomicrographs. The Florida palynomorph spectra and their chronological succession are quite similar to age-equivalent material from Portuguese Guinea and, in part, to material from North Africa. The palynological data suggest that the environment of deposition in north-central Florida was holomarine, and not lagoonal as was supposed before.