Komárek J., Kovacik L. Schizotrichacean cyanobacteria from central Spitsbergen (Svalbard) // Polar Biol., 2013. Vol. 36. P. 1811-1822.
Description and diagnosis of the Svalbard populations
Filaments relatively thin, with sheaths slightly distant from trichomes, containing 1-3(6) parallelly arranged trichomes, which are solitary or in fascicles, 3–4 lm wide. Sheaths are always colourless, not or indistinctly lamellated, sometimes slightly irregular or gelatinizing from outside. Trichomes cylindrical, usually not constricted at cross-walls, or rarely also cylindrical, but slightly widened towards their ends and slightly constricted. Cells rarely isodiametric, commonly up to 2 9 longer than wide, pale blue-green or greyish, often with irregular small polar granules, 0.8–1.2 lm wide. Type material deposited in the herbarium BRNM HY (Moravian Museum, Brno, Czech Republic).
Comments
S. borealis does not form macroscopic colonies. The colourless sheaths, cells with facultative polar granules and thickened filaments are characteristic of this species. Schizothrix borealis is also morphologically similar to S. thermophila Copeland, which, however, has an entirely different ecology (thermal springs). The comparison with some populations (concepts) of S. lardacea Gomont is also required. It is similar also to S. lacustris A. Braun ex Gomont (sensu Starmach 1973, particularly to his Fig. 379),
possibly also ecologically. We know typical S. lacustris, e.g. from Alpine lake localities. But it differs both ecologically and morphologically from S. borealis, especially in the form of its colonies.
