Aspects of late devonian and early carboniferous palynology of southern Ireland, IV morphological variation within Diducites, a new formgenus to accomodate camerate spores with two-layered outer wall

Abstract

In the Upper Devonian (Tournaisian 1a and 1b) of southern Ireland, camerate spores provided with a two-layered outer well are regular components of palynological assemblages. These forms are attributed to the formgenus Diducites Van Veen nov. gen. The four species recognised [D. plicabilis Van Veen nov. spec., D. versabilis (Kedo) Van Veen, nov. comb. et emend., D. poljessicus (Kedo) Van Veen, nov. comb. et emend., and D. mucronatus (Kedo) Van Veen, nov. comb. et emend.] are linked in the Diducites mucronatus morphon, since they show continuous variation in morphology.

In the present paper the taxonomy of the individual species of this morphon and the application of the morphon in both biostratigraphy and phytogeography will be discussed.