Recent foraminifera of Chipurupalle stream, east coast of India

Abstract

The Chipurupalle stream is a marginal marine environment near Visakhapatnam, east coast of India. The foraminifera, as well as seasonal variations in their abundance and distribution in the stream, have been investigated in relation to different ecological factors like salinity, temperature, pH and dissolved oxygen of waters in contact with the sediment, and texture and organic matter content of the sediments. In all, 39 species of foraminifera have been identified from the stream. Of them 17 species are never found in living condition in the stream and are not only scarce in occurrence but are confined to the confluence area. The remaining 22 species represented by living specimens comprise four agglutinated, four calcareous imperforate, and 14 calcareous hyaline forms. Ammonia beccarii (Linné), A. tepida (Cushman), Quinqueloculina seminulum (Linné), Elphidium simplex Cushman, Globigerina sp., and Miliammina fusca (Brady) are the only foraminifera which are common to abundant in occurrence in the stream. Ammonia beccarii and Quinqueloculina seminulum seem to reproduce in the Chipurupalle stream in December while Elphidium simplex does so in May, The former may also have a secondary bloom in May.