Leguminosae is the most diverse family in the savannas of Roraima, which are the largest savanna areas in the Brazilian Amazon. This paper presents a floristic survey and an analysis of the geographic distribution patterns of Leguminosae taxa in a savanna area at Boa Vista, Roraima (02º52´07´´N; 60º43´03´´W). The survey identified 80 taxa belonging to 38 genera. Six taxa are new records for the flora of Roraima. The best-represented genera were Aeschynomene and Chamaecrista, both with seven species each. Leguminosae-Papilionoideae was the most diverse subfamily based on the number of genera (24) and infrageneric taxa (53). The phytogeographical analysis revealed predominance of taxa with a Neotropical distribution. The savanna site analyzed represents a legume diverse area, because it concentrates 87% of legume diversity referred for the savannas of Roraima.
floristic survey; Guayana; Leguminosae; phytogeography