Recent changes (2008) in cyanobacteria taxonomy based on a combination of molecular background with phenotype and ecological consequences (genus and species concept)

Taxonomic classification is a method for recognizing and registering the world's organism diversity, in the context of continual changing knowledge about evolutionary (genetic) and ecological relations and phenotype variation. The present system of cyanobacteria must be modified according to combined markers, in which molecular data (as an indisputable genetic basis) should be correlated with biochemical, ultrastructural, phenotypic and ecological data. New data are necessary in order to correct or up date the system; thus, the classification must continually be revised and supplemented. The greatest problem is to transfer all modern data derived from molecular investigations to experimental research and establish the necessary and correct nomenclatural rules for scientific practice. The molecular approach must be the baseline for the reorganisation of our knowledge; however, it should explain and be in agreement with morphological and ecological variation of cyanobacterial genotypes. The present article summarizes the main conclusions, derived from modern cyanobacterial diversity studies.