Abstract
Light microscope (LM) and electron microscope (SEM and TEM) studies of Navicula florinae Moeller reveal that its valve structure possesses features typical of the recently established diatom genus Fallacia Stickle et D. G. Mann. The most important of these features are the presence of a conopeum and a lateral hyaline area. Its correct name is therefore Fallacia florinae (Moeller) Witkowski comb. nov. The ecology of F. florinae is considered briefly.