Primary description of surface water phytoplankton pigment patterns in the Bay of Bengal

►HPLC pigment analysis from the Bay of Bengal. ►Prokaryotes dominated in oceanic settings, flagellates at near coastal regions. ►Rainfall influence was reflected in changes in pigment patterns. ►Pigment index was not significantly related with dinoflagellate abundance. ►Simultaneous pigment and microscopic analyses are suggested.