New Selandian species of Glaphyrocysta and Spinidinium from offshore Northwest Europe.

This article presents the formal description of three dinoflagellate cyst species recovered from Selandian sediments in the Faroe-Shetland Basin and offshore Norway. These species have been recognized informally by the regional biostratigraphy community to support the sequence stratigraphic subdivision of Paleocene sediments and used as intra-Selandian markers but have never been formally described. This paper outlines the characteristic features and paleogeographical distribution of Glaphyrocysta granulosa sp. nov. and Glaphyrocysta shetlandensis sp. nov., and compares these taxa with known published species of Glaphyrocysta. Both new species of Glaphyrocysta have a sub-spherical/sub-circular outline with processes connected distally by irregular broad trabeculae terminations, however, G. granulosa has a tendency to have a wider body width and a relatively dense granulate central body ornamentation compared with G. shetlandensis which has significantly reduced surface ornament, and punctate wall structure. Spinidinium selandicum sp. nov. is stratigraphically older than the two new Glaphyrocysta species described and is characterized by having an unusually delicate ornamentation and very low sutural ridge which allows for comparison with other species of Spinidinium. The paleogeographical distribution of these new species covers an area ranging from the Faroe-Shetland Basin to the Vøring Basin (offshore Norway). • Three dinoflagellate cysts species from Selandian sediments are described. • All three species are important biostratigraphic markers across offshore Northwest Europe. • Presented taxa exhibit features distinctive from all other species described in the same genera. [ABSTRACT FROM AUTHOR]