Five species of Rhodophyceae collected for one year from Visakhapatnam coast were analysed for their Photosynthetic pigments. The environmental variables such as temperature, pH, salinity, light, dissolved oxygen, nitrite, phosphate and silicate were also measured for the same period at the same location of collection. Of the pigments analysed, Chl – a was higher in all the five species and it was followed by phycoerythrin in Pterocladia heteroplatos, Hypnea musciformis and Centroceras clavulatum and phycocyanin in Gracilaria corticata and Grateloupia lithophila. The distribution of pigments showed variations among the species. The higher content of pigments was found in April and June for G. corticata, it was in March for P. heteroplatos and January for C. clavulatum. The ratio of phycobilins to Chl – a also varied among the species. It was high in H. musciformis and C. clavulatum and P. heteroplatos and low in the remaining other two species. The environmental variables showed positive correlations with the pigments at significant levels. The Chl - a correlated positively with temperature, pH, salinity, light, nutrients and phycocyanin at P > 0.05 level. The phycoerythrin was correlated positively with pH, salinity, Phycocyanin and nitrite and phosphate at P > 0.05 level. The Phycocyanin was correlated positively with pH, salinity, dissolved oxygen, nitrate, phycoerythrin and Chl – a at P > 0.05 level.
