The little known pseudofilamentous cyanobacterium Wolskyella (Synechococcales)

The cyanobacterial genus and species Wolskyella filamentosa was described in the 1960's by G.G.Claus from freshwaters in South Africa, and the second species of this genus, the marine W. solitaria by Ehresmann and G.G.Claus from Oyster Bay, Long Island South, USA. Both species were not satisfactorily confirmed again and the whole genus has been considered questionable. Its unusual morphology resembles disintegration of trichomalous cyanobacteria into solitary cells, enveloped by a sheath. However, in recent years several populations corresponding to the genus Wolskyella were found in various aquatic freshwater habitats in distant areas over the world. The studied populations are presented in this article and the problematic status of this genus is discussed. Two distinct morphotypes from Australia (Queensland) and USA (Florida, Everglades) are described as new species.