APHANIZOMENON SCHINDLERI SP-NOV - A NEW NOSTOCACEAN CYANOPROKARYOTE FROM THE EXPERIMENTAL LAKES AREA, NORTHWESTERN ONTARIO

Aphanizomenon schindleri sp.nov., a new nostocacean, bluegreen, cyanop rokaryote (cyanobacterium), is described from artificially eutrophied Canadian Shield lakes in the Experimental Lakes Area, northwestern Ont ario. It is unique to low conductivity Canadian Shield waters to which nutrients have been added, and it became the dominant bloom species a fter years of phosphorus (P) and nitrogen (N) loading followed by N li mitation (N:P less than or equal to 5:1 by mass) (Findlay et al. 1994. Can. J. Fish. Aquat. Sci. 51:2254-2266). The new Aphanizomenon specie s appears to be most closely related to A. gracile but also resembles species of Anabaena with straight filaments. It differs from other spe cies of Aphanizomenon in cell dimensions, length and width of akinetes and heterocytes, and in akinete and end cell shape.