Distribution of brown seaweeds (Phaeophyta) in the Yucatan Peninsula, Mexico

Thirty five species of brown seaweeds (Phaeophyta) were found at 72 sites a round the Yucatan peninsula. Dictyota menstrualis, Lobophora variegata, and Dictyota pulchella were the most common species. Seven new records were re gistered for the three states comprising the Yucatan peninsula: Hincksia sa ndriana in Quintana Roo; Hydroclathrus clathratus, Dictyopteris delicatula, Dictyota menstrualis, and D. mertensii in Campeche; and Hincksia mitchelli ae. Ectocarpus rallsiae, and Sargassum cymosum in Yucatan. Twenty-eight spe cies not found in this study but reported by other authors were included. T wenty one percent of the species were not distributed on both the Caribbean (Eastern Quintana Roo) and the Gulf of Mexico (Northwestern Quintana Roo, Yucatan and Campeche) coastlines of the peninsula. However, species richnes s was similar on both coastlines of the peninsula (58 vs 54 species, respec tively). The northeastern tip of the peninsula (Cabo Catoche) is suggested as the coastal boundary between the Caribbean and the Gulf of Mexico phycof lora of the Yucatan peninsula.