1Institute of Oceanography, University of Gdansk, Al. Pilsudskiego 46, 81-378 Gdynia, Poland
2Institute of Marine Sciences, University of Szczecin, Waska 13, PL-71-415 Szczecin, Poland
Abstract:
Presented are results of morphological (LM and SEM) and taxonomical investigations on very small-sized Navicula spp. from the brackish waters of the Gulf of Gdansk and some freshwater affluents. Detailed studies revealed that most of the taxa in question are either new for science or previously described but rather poorly known. Dominant in that assemblage of extraordinarily small-celled Navicula species, specimens mostly below 10 μm in length, are Navicula germanopolonicaWitkowski & Lange-Bertalot and Navicula paulschulziiWitkowski & Lange-Bertalot as established taxa. New for science are Navicula aleksandrae, Navicula bozenae and Navicula viminoides ssp. cosmomarina. From common freshwater habitats no species are known that could be confused with the new taxa.