Marine algal flora of Formigas Islets, Azores.

A total of 320 specimens are registered (including taxa identified only at generic level) belonging to 90 taxa of macroalgae, from which 70 were diagnosed at species level. The confirmed species comprise 39 Rhodophyta, 12 Chlorophyta and 19 Ochrophyta (Phaeophyceae), distributed in 22 orders (13 Rhodophyta, 3 Chlorophyta and 6 Ochrophyta) and 37 families (24 Rhodophyta, 6 Chlorophyta and 7 Ochrophyta). Sixty-one species represent new records for the Islets, from which Botryocladia macaronesica Afonso-Carrillo, Sobrino, Tittley & Neto and Laurencia viridis Gil-Rodriguez & Haroun are Macaronesian endemisms. Most species are native to the Azores, but six have an uncertain origin and four are introduced (the Rhodophyta Asparagopsis armata Harvey; Laurencia dendroidea J.Agardh; Neoizziella divaricata (C.K.Tseng) S.-M.Lin, S.-Y.Yang & Huisman and the Ochrophyta Hydroclathrus tilesii (Endlicher) Santiañez & M.J.Wynne).