Taxonomy and distribution of Sargassum ( Phaeophyta ) in the Gulf of Thailand

Abstract

Ten speci es of Sargassum (Sargassaceae, Phaeophyceae) were found along the Gulf of Thailand. Morphological characteristics of Sargassum baccularia (Mertens) C.A. Agardh, S. binderi Sonder, S. cinereum J.G . Agardh, S. crassifolium J.G . Agardh, S. longifructum Tseng et Lu, S. oligocystum Mont agne, S. polycystum C.A. Agardh, S. siliquosum J.G. Agardh, S. swartzii (Turner) C.A. Agardh and one unidentified species were examined and are described in detail. The most common species were S. polycystum distributed widely in almost all the study sites, S. crassifolium restricted to Prachuap Khirikhan Province, S. longifructum restricted to Chumphon Province, S. siliquosum restricted to Surat Thani Province and one unidentified species restricted to Songkhla Province. Three species ( S. cinereum, S. longifructum and S. swartzii ) are new records for the algal flora of Thailand. Five species ( S. baccul aria, S. cinereum , S. longi fructum , S. polycystum and the unidentified species) belong to the section Zygocarpi cae (J.G. Agar dh) Setchell.