Living coccolithophorids from the Arabian Sea

Abstract

Coccolithophorids collected from the euphotic zone in the Arabian Sea during the tail end of summer monsoon (Sept. 20 to Oct. 06, 1992) were studied. Nineteen species were recorded, most abundant among them were, Emiliania buxleyi, Umbellosphaera irregularis, Umbilicosphaera sibogae var. foliosa and Gephyrocapsa oceanica. Low fertility of water during September-October is believed to have caused tha abundance of E. buxleyi and U. irregularis. It has also been observed that malformation of E. buxleyi are common during the summer monsoon upwelling period. It was also observed that the overall coccolithophorid density decreases from south to north. Higher coccolithophorid densities in the subsurface depths are attributed to suspected blooms and thermocline depth