Abstract
A red alga, (‘Dasysiphonia’, Dasyaceae, Rhodophyta), was recorded for the first time in Norway in 1996. The species is identical to an alga, first observed in Europe from the coast of the Netherlands in 1994, probably introduced from the North Pacific. A brief description and the seasonal development of the Norwegian plants are given. In 1997–99 it was found on 15 new sites in the Hordaland and Sogn og Fjordane counties. It is assumed that the species spread fast, and in a few years will be a common alga on a larger part of the Norwegian coast.
