Freshwater planktic Chroococcales (Cyanoprokaryota) from North-Eastern Australia: a morphological evaluation
Mc Gregor, Glenn B.; Fabbro, Larelle D.; Lobegeiger, Jaye S.
Planktic cyanoprokaryotes of the order Chroococcales are described from 192 sites in north-eastern Australia. Despite the diversity of freshwater biotopes, and increasing evidence of seasonal cyanoprokaryote dominance in planktic habitats, particularly man made reservoirs, this is the first detailed study documenting the cyanoprokaryote microflora from this region. Over five thousand samples were observed from which 54 Chroococcalean species were recorded representing four families. Sampling locations included natural lakes, man made reservoirs and weir pools, rivers and streams. The majority of the taxa could be regarded as cosmopolitan, followed by tropical/subtropical taxa and temperate taxa. The most common genera recorded included Aphanocapsa, Cyanodictyon, Myxobaktron, Merismopedia, and Microcystis. The highest taxon richness occurred in man-made lakes and reservoirs, followed by natural lakes, and streams and rivers. Fifty three taxa including three newly described species (Aphanocapsa annulata sp. nova, Gloeothece lacustris sp. nova, Gloeocapsa planctonica sp. nova) are presented including information on their morphological variability, ecology and distribution.