REVISION AND TYPIFICATION OF BRAZILIAN AUGUSTA (RUBIACEAE, RONDELETIEAE), WITH ECOLOGICAL OBSERVATIONS ON THE RIVERINE VEGETATION OF THE CERRADO AND ATLANTIC FORESTS

A revision of Brazilian Augusta and general comments on the systematic s of this genus are presented. The complex taxonomic history of this t axon has caused confusion over its correct nomenclature. The peculiar geographic distribution of Augusta has stimulated field observations a nd analysis of the ecology of the Brazilian ecosystems where this taxo n occurs, which are here presented. The five Brazilian species of Augu sta described by Pohl are here treated as ecotypes of A. longifolia. T his species has two distinct varieties: var. longifolia, widespread th roughout the Brazilian cerrado, and var. parvifolia, endemic to the At lantic forest near Rio de Janeiro. Typification, list of representativ e specimens, and distribution map of A. longifolia are also included.