MARINE-ALGAE OF NORTHERN SENEGAL - THE FLORA AND ITS BIOGEOGRAPHY

The subtidal marine algal flora of northern Senegal has been character ized based on a literature review and collections made during December and February, 1993-94. At present, 242 species are listed from northe rn Senegal of which 80 species were found in this study (16 Chlorophyt a, 12 Phaeophyta and 52 Rhodophyta). This includes 29 species not prev iously recorded for Senegal and 8 species previously unknown from West Africa. The biogeographic affinities of Senegal are primarily with th e more temperate floras to the north, and there is a sharp transition in species composition between northern Senegal and regions to the sou th. The relative absence of tropical species is explained by southward directed ocean currents and the occurrence of major areas of brackish water and mangrove communities to the south.