The dissertation is a revision of the US plant genus Axinaea (Melastomataceae, Merianieae). The genus contains 41 species, eight of which here described as new to science. Forty of the species occurs exclusively in the Andes mountain range from Venezuela in the north to Bolivia in the south. A single species, A. costaricensis, reach into Central America. The greatest concentration of species are present in the south of Ecuador and northern Peru.
The genus Axinaea belonging to the tribe Merianieae, and among them they are a peculiar genus by having swollen, spherical to elliptical pendants on the stamens. It appears to be a secondary characteristic, as they are all derived from a common ancestor. A single species, A. macrophylla, is described for the first time ever.
Most species are very limited in their distribution. Twenty-eight species occur only in one country, nine are in two countries, three in three, and one species, Axinaea floribunda, occurs in four countries. The high degree of endemism and threat from vegetation fires, logging and deforestation to provide arable land means that the habitats where Axinaea occurs are threatened. Therefore Axinaea is a seriously endangered species.