Taxonomy and biostratigraphy of late cretaceous and Paleogene triatriate pollen from South Carolina

This paper discusses the morphology, taxonomy, and stratigraphic occurrences of 24 species and species groups of triatriate pollen. The material is from uppermost Paleogene rocks of the U. S. Geological Survey Charleston Project Deep Corehole No. 1 (Clubhouse Crossroads corehole), Dorchester County, South Carolina. The 24 pollen types are assigned to seven genera: Momipites, Plicatopollis, Platycaryapollenites, Platycarya, Subtriporopollenites, Carya, and Casuarinidites. The definitions of the first three of these genera are emended in this paper, and five new species are proposed: Momipites fragilis, Momipites strictus, Momipites? annulatus, Plicatopollis cretacea, and Casuarinidites sparsus. The stratigraphically lowest occurrence of juglandaceous triatriate pollen in the core is in rocks of Austinian (possible Santonian) Age, and altogether seven triatriate types are known from the Upper Cretaceous. The maximum diversity of these pollen types is in the upper Paleocene and lower Eocene (13–15 forms per stratigraphic level). Eleven apparently significant pollen‐stratigraphie events have been determined on the basis of first, last, and peak occurrences of triatriate pollen in the Austinian‐Chickasawhayan interval of the core.