ARIADNAESPORITES AND CAPULISPORITES - WATER-FERN MEGASPORES FROM THE UPPER CRETACEOUS OF CENTRAL-EUROPE

Megaspores with prominent acrolamellae and body-processes (appendages) from Upper Cretaceous (upper Turonian-Santonian) deposits in south Bo hemia, Czech Republic, originally referred by Knobloch to Arcellites m edusus (Dijkstra) Potter are redescribed as Ariadnaesporites pilifer s p. nov, and Capulisporites klikovensis sp. nov. based on SEM and TEM s tudies. Although differing in gross morphology and to some extent in w all-structure, they are sufficiently similar to suggest that they repr esent closely related plant taxa. These may have belonged to an extinc t group of ''water ferns'' rather than to either of the modern hydropt erid families Marsileaceae and Salviniaceae.