Marine benthic algae of Norfolk Island, South Pacific

Abstract

The marine benthic algae of Norfolk Island are documented and 60 of the 236 species are illustrated. All records are fully referenced, and type localities, local distribution and notes on taxonomic and biogeographic affinities of each species are given. Of the 236 taxa, 41 species are Chlorophyta, 41 are Phaeophyta and the remainder (154) are Rhodophyta. Apart from several undescribed taxa, none is endemic to the island, although Solieria anastomosa and Dasya fruticulosa are apparently restricted to Norfolk and Lord Howe Island, the two islands presently sharing 106 species (almost half the Norfolk marine flora and one-third that of Lord Howe). Although there are some species for which Norfolk Island represents a major range extension into or within the Pacific (Dasycladus ramosus, Halicoryne wrightii, Anotrichium anthericephalum, Herposiphonia arcuata and Polysiphonia japonica), a con- siderable number of the species are shared with the Great Barrier Reef and the New South Wales coastline as well as Lord Howe Island. Major northern range extensions are recorded for the large temperate brown alga Ecklonia radiata, and possibly Phyllospora comosa and Durvillaea antarctica, although the island more typically hosts numerous tropical algae such as Trichogloea requienii and members of the green algal order Dasycladales including Halicoryne wrightii, Bornetella nitida and Neomeris annulata. As a consequence of this survey, the two rhodymeniacean species Chrysymenia ornata and C. digitata are considered to be conspecific.