| Four new species of Sargassum belonging to the Series Platycarpae of the glomerulate Sargassum are described, namely, Sargassum yongxingenes, collected from Yongxing Island, Xisha Islands in March 8, 1958; Sargassum sanyaense, collected from Dadonghai, Sanya City, Hainan Islands in April 15, 1976; Sargassum dazhouense, collected from Dazhou Island, Sanya City, Hainan Islands in June 12, 1957 and Sargassum megalocystum, collected from Dazhou Island, Sanya City, Hainan Islands in June 12, 1957. The type specimen are all deposited in the Herbarium of the Institute of Oceanology, Chinese Academy of Sciences in Qingdao, China.
1 Sargassum yongxingense Tseng et Lu sp. nov. (Fig.1 a, b; Plate I: l) is mainly characterized by its secondary branches and branchlets with conspicuously raised glandular dots on the surface, its small, spatulate, obovate leaves, duplicate at the apex forming cup-like structures, its spherical vesicles, usually with earlike or small foliar wings on the both sides and its compressed receptacles generally cymosely arranged in glomerule. It is closely related to Sargassum duplicatum Bory differing in its secondary branches and branchlets with conspicuously raised glandular dots, its smaller leaves, and vesicles usually surrounded by a small foliar wing.
2 Sargassum sanyaense Tseng et Lu sp. nov. (Fig.2 a,b,c; Plate I: 2) is mainly characterized by its secondary branches and branchlets with some conspicuously raised glandular dots., its leaves usually double serrate at the apices, its vesicles spherical or subspherical, usually surrounded by a small foliar structures and its receptacles compressed at upper parts, subcylindrical below. It is closely related to Sargassum cristaefolium C. Agardh differing in its raised glands on the secondary branches and branchlets. It is also closely related to Sargassum yongxingense Tseng et Lu differing in its leaves double serrulate at the apices.
3 Sargassum dazhouense Tseng et Lu sp. nov. (Fig.3 a,b,c; Plate I: 3) is mainly characterized by its oblong, sometimes obovate leaves, obtuse or sometimes with double serrulate at apex; vesicles spherical, usually forked acute at apices; receptacles flattened. It is closely related to Sargassum megalocystum Tseng et Lu differing in its spherical. sometimes subspherical, vesicles usually forked or acute at apex and thinner
spiny fringe margins and larger oblong leaves.
4 Sargassum megalocystum Tseng et Lu sp. nov. (Fig.4 a,b,c; Plate I: 4) is mainly characterized by its small obovate leaves, sometimes oblong, rounded, sometimes double serrulate at apex; its very large, oblong vesicles, slightly acute at apex, usually surrounded by irregularly spiny fringe margin; and its flattened receptacles, sometimes triqueirous in its upper parts. It is related to Sargassum cristaefolium C. Agardh differing in its very large, oblong vesicles, almost as large as the surrounding leaves, usually surrounded each by a irregularly spiny fringe margin. |
