Sargassum lanceolatum Greville, 1848 [1848–1849]: 431–432, pl. XIII: upper figs. 1–5, nom. illeg. (type locality: India).—Greville, 1850: 90, pl. VIII: upper figs. 1–5.
Sargassum cinctum J. Agardh var. lanceolatum Grunow in Askenasy, 1888: 28 (`lanceolata').
Sargassum coriifolium J. Agardh var. lanceolatum (Grunow) Grunow, 1915 [1915–1916]: 436 (`lanceolata') (including Indian Ocean records).—K. Srinivasan, 1965: 243.— K. Srinivasan, 1967: 139, fig. 17.
Sargassum odontocarpum Sonder var. lanceolatum (Grunow) P. Silva.
INDIAN OCEAN DISTRIBUTION: Australia, India, Sri Lanka.
Note: In 1848, J. Agardh and Greville independently described new species of Sargassum bearing the epithets echinocarpum and lanceolatum, with J. Agardh's names having priority by a few months. Sonder (1871: 43), finding specimens from Queensland and Singapore that he believed to be conspecific with S. echinocarpum Greville, proposed the substitute name S. odontocarpum. In his monograph of Sargassum, J. Agardh (1889: 96) merged the two Greville species under the new name S. coriifolium, apparently being unaware of Sonder's earlier proposal. Sargassum coriifolium is thus a superfluous and illegitimate name that must yield to S. odontocarpum.In treating Greville's species as varieties, first of S. cinctum then of S. coriifolium, Grunow published trinomials. Because Greville's species bear illegitimate names, however, they cannot serve as basionyms. Thus, S. cinctum var. echinocarpum Grunow and S. cinctum var. lanceolatum Grunow are treated as nomina nova in accordance with Art. 58.3.