The floristic composition of forest remnants in northeastern São Paulo, Brazil, is still poorly reported. A floristic and phytosociological survey of a gallery forest in Cristais Paulista Municipality was carried out to characterize the flora and compare it to other riverine forests. The phytosociological aspects of the remnant were obtained by the point-centered quarter technique in four transects running parallel to the river bed, considering 90 points, equidistant ten meters, and sampling all individuals with pbh > 15 cm. All fertile specimens not included in the phytosociological sample were also identified. A total of 68 species and 37 families were found, with 53 species and 34 families reported in the phytosociological survey. The species diversity index (H') was 3.17 nats individual-1 and the most important species (IV) were Virola sebifera, Protium heptaphyllum, Tapirira guianensis and Copaifera langsdorffii. Comparison to other riverine forests showed greater floristic similarity with those found throughout the Rio Grande basin, possibly because of similar climates, and with forest remnants throughout Central Brazil due to the drainage network that provides a migratory route for the plant species. Many "cerrado" (Brazilian savanna) species were found in the gallery forest and this fact reinforces the role played by Brazilian savanna vegetation in the biodiversity of gallery forests.
Cerrado (Brazilian savanna); species diversity; riparian forests; floristic similarity
