Dinoflagellate cysts from the Eocene of the London and the Hampshire Basins, southern England.

Abstract

Abstract Dinoflagellate cysts have been recorded and studied from the upper part of the London Clay and overlying Bagshot Formation sensu stricto of early‐middle Eocene age from Baughurst, Shapley Heath, Virginia Water, Chobham Common and the Isle of Sheppey in the London Basin and from the early‐middle Eocene Bracklesham Group at Bracklesham Bay in the Hampshire Basin. Stratigraphically significant species have been used to classify the studied sections into dinoflagellate assemblage zones after the scheme of Bujak et al. (1980). Correlations indicate the diachronic nature of the relevant lithostratigraphic boundaries in the London Basin and correspondence of geological events in the two basins. The Systematics section deals mainly with new and reattributed taxa which include one new genus, nine new species and two new subspecies. The new taxa are: Achomosphaera improcera n. sp., Adnatosphaeridium williamsii n. sp., Apectodinium cornufruticosum n. sp., Areosphaeridium polypetellum n. sp., Biconidinium n....