Little known tropical Chroococcus species (Cyanoprokaryotes)

Nine little known or new species of the cyanoprokaryotic genus Chroococcus from tropical regions are presented. Two of them, Ch. polyedriformis Schmidle 1902 and Ch. mipitanensis (Woloszyńska 1912) Geitler 1925, were described as early as in the first decades of this century, but ignored by later authors, probably owing to the authority of Geitler who omitted these taxa in his world monograph from 1932. Both these species occur in tropical freshwater biotopes over the world and were repeatedly published under different incorrect names. Recently, they were found in Central American localities. Five species, differing slightly from the known and described taxa, were found from the metaphyton of stagnant waters in Cuba and in the coastal areas of Mexican Gulf in Mexico (Papaloapan basin); their variability and morphology are discussed. One new species, Ch. deltoides, is described. Two planktic species (from the subg. Limnococcus) are described from large African lakes. Ch. catenatus from L. Edward (E Africa) and Ch. cronbergae from the Kariba reservoir.