Abstract Detailed palynological examination of the Nkporo Shales based on the occurrence of both miospores and organic-walled microplankton, mainly dinoflagellate cysts, has been carried out for the first time. The recovered palynofloral assemblage essentially displays the typical characteristics of the Senonian Palmae province comprising a majority of the Campanian-Maastrichtian elements recorded from tropical-subtropical regions of South America, Africa and India. Based on the data, a late Campanian-Maastrichtian age range is established for the Nkporo Shales succession on the Calabar Flank. The palynofloral distribution allows for a fine stratigraphic differentiation of the sequence. Dinoflagellate cyst species which define the late Campanian include Coronifera tubulosa and Andalusiella polymorpha. The early Maastrichtian is characterised by an assemblage comprising mainly the miospore species Monocolpites marginatus, Longapertites spp. and the dinoflagellate cyst taxon Dinogymnium. The mid-Maastrichtian is defined on the basis of an increase in the frequency of the miospore species Buttinia andreevi while the late Maastrichtian is defined by the presence of the miospore species Spinizonocolpites baculatus, Aquilapollenites minimus, Proteacidites miniporatus, Syncolporites marginatus and the dinoflagellate cyst species Cordosphaeridium fibrospinosum.