This paper analyzes the taxonomy and distribution of the genus Caulerpa on the coast of Pernambuco (07º30'S; 09º00'W) and in the Fernando de Noronha Archipelago (03º51'S; 32º25'W). Sampling was carried out on the coast of Pernambuco from April/2004 to November/2005, in the intertidal zone of 32 beaches. On Fernando de Noronha collections were made in June/2006 in the intertidal and infralittoral (10, 15 and 21m depth) regions of eight beaches. Exsiccata of Caulerpa from the Professor Vasconcelos Sobrinho Herbarium (PEUFR) were also examined. The results showed that the genus Caulerpa is represented on the coast of Pernambuco state by 19 infrageneric taxa. Some species had restricted distributions such as C. kempfii Joly & Pereira, C. lanuginosa J. Agardh and C. serrulata (Forssk.) J. Agardh. Three infrageneric taxa were registered for the Fernando de Noronha Archipelago.
seaweeds; Brazil; Caulerpa; floristic survey; Northeast
