Taxonomic Revision ofSpiranthera(Rutaceae)

Abstract

Abstract—Spiranthera(Rutaceae, Galipeeae) is a neotropical genus, recognizable mainly by the presence of trifoliate leaves, pentamerous flowers, exappendiculate filaments, spirally revolute anthers lacking a basal appendage, a campanulate disk, and anelongated gynophore. Species in this genus are mostly sciophilous treelets from South American rainforests, except forSpiranthera odoratissima, the most widespread species, which is a shrub inhabiting savannic formations and showing the widest morphological variation within the genus. In this taxonomic revision we present an extensive morphological analysis of the genus based on data from field work and from herbaria, an identification key, and descriptions and illustrations of the six species here recognized, including a new one from Iquitos, Peru. Also, we present updated information on the geographic distribution of the species, their habitats, and their morphological variability.