Seaweeds are important components of tropical reef systems. The presen
t paper deals with the Chlorophyta, Phaeophyta and noncoralline Rhodop
hyta collected by the first author in the Spermonde Archipelago, SW Su
lawesi, Indonesia, during the Buginesia-III project (November 1988 - N
ovember 1990). Additional collections from this area by Keblusek (July
1991-October 1991) were also studied and the results are incorporated
in the present paper. The results of the present study are compared w
ith those of the Siboga Expedition (1899-1900), of the Danish Expediti
on to the Kei Islands (1914-1916), and of the Snellius-II Expedition (
1985). In total, 199 taxa (80 Chlorophyta belonging to 21 genera, 36 t
axa of Phaeophyta belonging to 11 genera, 83 noncoralline Rhodophyta b
elonging to 40 genera, and about 35 taxa of coralline algae) were coll
ected. Of these, 72 taxa are new records for Indonesia (17 Chlorophyta
, 20 Phaeophyta, and 35 noncoralline Rhodophyta). Caulerpa buginense a
nd Udotea flabellum f. longifolia are newly described. Keys to the gen
era, species, and forms are provided, and remarks on the economic pote
ntial of some of the seaweeds are included.