A revision of the genus Geitlerinema and a description of the genus Anagnostidinema gen. nov. (Oscillatoriophycidae, Cyanobacteria)

Abstract

The simple filamentous cyanobacterial genus Geitlerinema is heterogeneous. At least two distinct phylogenetic clades can be derived from the set of most common freshwater Geitlerinema species. Our revision is based on the original description of the type species G. splendidum aka Oscillatoria spendida and on molecular sequencing of morphologically relevant strains. The revised Geitlerinema contains only one species according to morphological similarity with its original description. Consequently, the majority of other freshwater species inferred from molecular sequencing of 16S rRNA gene and 16S–23S ITS analysis (related both genetically and morphologically to G. pseudacutissimum) must be classified as a special taxon on the generic level. The name Anagnostidinema is proposed for this genus, which was selected in memory of the prominent late cyanobacterial specialist Konstantinos Anagnostidis. The genetic position, short review and characteristics of the newly defined genus Anagnostidinema is presented in this paper. The taxonomy of the rest of species (including the marine taxa), which are currently unable to be classified taxonomically with certainty, remain to be resolved in future studies.