The stratigraphic distribution of organic-walled dinoflagellate cysts in the Cretaceous and Tertiary

Abstract

All information concerning the stratigraphic distribution of organic-walled dinoflagellate cysts in the Cretaceous and Tertiary sediments of the world, published prior to 1974, has been critically assessed. Stratigraphically reliable records are presented in tabular form; stratigraphical subdivision to stage or formation is incorporated wherever possible. Records of doubtful authenticity are commented on and questions of stratigraphic and taxonomic interest are discussed in the text. A new family, Family Florentiniaceae nov. fam., is erected, and the following new taxonomic combinations are proposed: Astrocysta ampla (Harland, 1973) nov. comb.; Cooksoniella larjakense (Vozzhennikova, 1967) nov. comb.; ? Florentinia truncigera (Deflandre, 1937b) nov. comb.; Phthanoperidinium pannonium (Lentin and Williams, 1973) nov. comb.; Spiniferites scabrosus (Clarke and Verdier, 1967) nov. comb. and Veryhachium hermesinoides (O. Wetzel, 1940) nov. comb., the latter being now considered to be an acritarch. The rejection is proposed of the following species, which were nomenclaturally superfluous when published: Astrocysta koslowskii (Górka 1963) Davey, 1970; Gonyaulacysta fragosa Brideaux, 1971; Hystrichosphaeridium brideauxi Lentin and Williams, 1973; Oligosphaeridium diastema Singh, 1971 and Pseudoceratium regium Singh, 1971. Reasons are given for the rejection of the following generic reallocations: Hystrichodinium voigti (Alberti, 1961) Corradini, 1973 and Tenua anaphrissa (Sarjeant, 1966c) Benedek, 1972. Rhombodinium Gocht, 1955 is considered to be best treated as a subgenus of Wetzeliella Eisenack, 1938 emend. Williams and Downie, 1966b as originally proposed by Alberti, 1961.