Diversity and Taxonomic studies of Cyanophyceae in Tirunelveli district Tamil Nadu India

: The class Cyanophyceae are the simplest living autotrophic prokaryotes. In the present study the diversity of fresh water algae (Cyanophyceae) Tirunelveli District seven sites were selected for the collection of algae. A total number of 32 species were collected from different localities. These algal taxa are classified into four families such as Chroococcaceae Oscillatoriaceae Nostocaceae and Rivulariaceae. 5 species belong to 4 genera are under Chroococcaceae 13 species of 5 genera under Oscillatoriaceae 10 species of 5 genera under Nostocaceae and 4 species of 4 genera under Rivulariaceae. Classwise percentage contribution study of algae reveals that highest contribution was of Chroococcaceae (15.62%) Oscillatoriaceae (40.62%) Nostocaceae (31.25%) and Rivulariaceae (12.5%)