Abstract
An investigation of the algal vegetation in the Florø district was undertaken in 1997. Representative samples were selectively collected at exposed and sheltered sites in February and September. New to Norway were: Acrochaete heteroclada, A. inflata, Aglaothamnion cf. pseudobyssoides, and Ulvella setchellii. Ceramium botryocarpum, C. pallidum and C. siliquosum have not previously been recorded in Norway, but may have been reported under different synonyms. Epicladia philipsii, Gracilariopsis longissima, Pseudendoclonium dynamenae, and Syncoryne reinkei were recently separated from other species and old records of these may in part cover the new species. The study extends the known northern boundary of distribution along the Norwegian west coast for 20 species. Reproductive male plants of Rhodochorton purpureum were observed, probably for the first time in nature. A summary of all species known to occur in the district is given and includes 33 Nostocophyceae, 121 Bangiophyceae, 64 Fucophyceae, and 56 Chlorophyceae. The distribution of some species in certain west Norwegian districts are discussed in relation to relatively warm winter temperatures.