Parrotfishes of the genus Scarus in southwestern Atlantic oceanic reef environments: occasional pulse or initial colonization?

Two Brazilian endemic parrotfishes of the genus Scarus are recorded for the first time in oceanic reef environments of the Southwestern Atlantic. A few juveniles, and initial and terminal adults of Scarus trispinosus were observed at Rocas Atoll and one adult was recorded at Fernando de Noronha Archipelago. Conversely, an established population of Scarus zelindae was found in the middle of the Vitoria-Trindade Chain, at the Davis seamount. Since dispersal potential is not a limitation for the pantropical distribution of the genus Scarus, historical and contemporary ecologic features are possibly the main processes driving these unique records in the Southwestern Atlantic. Here, we highlight the potential ecological reasons of such intriguing biogeographic pattern.