Micrandra Benth. is a Neotropical genus with its center of diversity in the Amazonas River basin. The species are trees, rarely shrubs with unisexual, apetal flowers, 3-10 stamens, schizocarpic fruits, and seeds either with or without a caruncle. As part of a review of this genus, collections of Brazilian and foreign herbaria were consulted, including type specimens. Nine species are recognized: Micrandra elata, M. gleasoniana, M. inunatada, M. lopezii, M. minor, M. rossiana, M. siphonioides, M. sprucei and M. spruceana. Micrandra elata and M. minor are new records for Colombia, and M. spruceana for Acre and Mato Grosso States, Brazil. Two species are considered new synonyms and two new lectotypes are designated. The morphological relationships between Cunuria Baill. and Micrandra are discussed. New morphological data and ilustrations are provided for M. sprucei. An identification keys to species, geographical distribution data and comments on the species are presented.
Amazonian flora; Crotonoideae; Cunuria; Micrandreae
