THE NODULARIA STUDIES .2. TAXONOMY

This second part of the studies on the strains and populations of the cyanoprokaryotic (cyanophyte/cyanobacterial) genus Nodularia (1st part : Introduction, fine structure; see SMARDA et al. 1988) concerns Nodul aria taxonomy. Two distinct groups of species were recognized within t his genus, differing in cytomorphological features and in ecology. The presence or absence of gas vesicles (and of their clusters = aerotope s) is a prominent differentiating marker of both these groups. In our materials several types at the species level were recognized, characte rized by morphological limits and by their various ecological niches. Three benthic species lacking aerotopes (N. harveyana, N. sphaerocarpa , N. willei) and four planktic, aerotopated species (N. baltica, N. sp umigena, N. litorea, N. crassa) are revised using our samples. The dif ferent size and density of gas vesicles as taxonomic features are disc ussed. A review of the genus is presented.