Diversity, morphology, and distribution of Coelastrum (Chlorophyceae) in plankton of lakes in the environs of Vilnius [Coelastrum genties žaliadumblių (Chlorophyceae) įvairovė, morfologijos bruožai ir paplitimas Vilniaus apylinkių ežerų planktone]. – Botanica Lithuanica, 9(1): 25–41

oelastrum species were investigated in the plankton samples from 22 lakes located in Vilnius region during 1997–1999. Six species – Coelastrum microporum, C. astroideum, C. cf. pseudomicroporum, C. reticulatum, C. proboscideum, C. cambricum – were identified. C. astroideum (13 lakes) and C. microporum (11 lakes) are the most spread species in Vilnius region. C. cambricum was found only in swamp lakes. C. cf. pseudomicroporum was recorded for the first time from Lithuanian terrestrial waters. C. sphaericum and C. indicum were found in plankton of water bodies from other regions of Lithuania. Species descriptions with original drawings, morphological features, distribution, and comments are provided.

Keywords: Chlorococcales, Coelastrum, plankton, diversity, morphology, distribution, lakes, Lithuania.