EUASTRUM-VIGRENSE (CONJUGATOPHYCEAE, CHLOROPHYTA) - A LIGHT AND ELECTRON-MICROSCOPIC APPROACH

In 1927 Ryppowa encountered a rather curious looking Euastrum that she decided to be a new species: Euastrum vigrense. Krieger (1937), howev er, thought it to be a ''monstrous form'' of Euastrum crassum and clas sed it as Euastrum crassum (Breb.) Kutz. ex Ralfs var. vigrense (Rypp. ) W. Krieger. In 1991 Handke collected some cells of this rare taxon i n Sweden and established clonal cultures. By means of light and electr on microscopical observations the variability within the different str ains was investigated. After comparison with two strains of Euastrum c rassum from our culture collection it seemed appropriate to use Ryppow a's description as a legal name.