Revision of the late Famennian miospore zonation scheme in eastern Belgium

Abstract. New palynological data have been obtained from the Late Famennian Evieux and Comblain au Pont Formations of the Chanxhe section located in the Ourthe Valley in the eastern part of the Dinant Basin. In the light of this new data the stratigraphic ranges of several zonally important miospore taxa are now significantly different to those previously recorded. This has necessitated a re-evaluation and revision of the late Famennian miospore zonation scheme for this region. Apiculiretusispora verrucosa and Vallatisporites hystricosus are now found to occur below the inception of Retispora lepidophyta. Consequently, a new biozone, the Apiculiretusispora verrucosa–Vallatisporites hystricosus VH Biozone is described for the late Fa2c interval. The problematical relationship between the Retispora lepidophyta– Apiculiretusispora verrucosa LV Biozone and the Retispora lepidophyta–Knoxisporites literatus LL Biozone is resolved, and part of the LL Biozone is now considered equivalent to the LV Biozone, which it consequently replaces. The Retispora lepidophyta–Indotriradites explanatus LE Biozone is recorded from the upper part of the Comblain au Pont Formation. A continuous succession of miospore zones is now established for the late Famennian Fa2c/Fa2d interval which permits more accurate correlations with other regions in Europe and North America. Correlation with the standard conodont biostratigraphy shows that the base of LL Miospore Biozone is correlated with the middle or late expansa Conodont Biozone and the base of LE Miospore Biozone with the early to middle praesulcata Conodont Biozone.