Contribuição ao conhecimento da Flora do Aripuanã (Mato Grosso). I. FanerógamasA list of species from Aripuanã (MT) flora is given by the authors. The material listed is only of the fertile plants collected belonging to the groups of Gymnospermae and Angiospermae. They were collected during the months October (1973) and September and October (1975). The families with most number of species in flower or fruit in September ond October were Moraceae, Leguminosae and Chrysobalanaceae.