Some rare and interesting green algae (Chlorophyta) from subalpine Tatra lakes (High Tatra Mountains, Poland)

Five green algal taxa rarely occurring in the world were found in subalpine lakes of the High Tatra Mountains in Poland. These are Actinastrum gracillimum G.M. Sm. var. elongatum (G.M. Sm.) Fott, Monoraphidium tatrae (Hindák) Hindák, Pediastrum braunii Wartm. in Wartm. et Schenk, Scotiella tuberculata Bourr. var. tuberculata and Thelesphaera olivacea (Beck-Mannag.) Fott. The taxa are described and illustrated with light micrographs and drawings. A review of their distribution in the world is presented.