Abstract:
Four species of Sargassum are reported from the east coast of the Gulf of Thailand. They are
Sargassum baccularia (Mertens) C.A. Agardh, S. binderi Sonder, S. oligocystum Montagne, and S. polycystum
C.A. Agardh. The common species are S. binderi, S. oligocystum and S. polycystum distributed in all the study
areas while S. baccularia has been found only in Chantaburi and Trat Province. S. baccularia is similar to
S. polycystum but lacks spines on the axis and secondary holdfast. S. polycystum has a secondary holdfast
transformed from the primary branch on the stem. Of the three species reported, S. baccularia, S. binderi and
S. oligocystum are new records for Thailand.
