A floristic survey of Acanthaceae is presented for the Mata do Paraíso Forest Reserve in the city of Viçosa, state of Minas Gerais, Brazil. The vegetation is mainly composed by forests belonging to the Atlantic Rain Forest Complex. Four genera and six species are recognized: Geissomeria schottiana Nees, Justicia scheidweileri V.A.W. Graham, Mendoncia velloziana Mart., Ruellia brevifolia (Pohl) C. Ezcurra, R. menthoides (Nees) Hiern, and R. subsessilis (Nees) Lindau. R. menthoides is a new record for the state of Minas Gerais. Identification keys for genera and species are provided, as well as descriptions, illustrations, geographic distributions, and comments on the taxonomic problems, uses and habitats of the species.
Acanthaceae; floristics; Minas Gerais; Southeastern Brazil; taxonomy