New taxa and nomenclatural notes on the flora of the Marojejy massif, Madagascar.V. Cunoniaceae: Weinmannia

Sixteen species of Weinmannia (Cunoniaceae) are recognized in a treatment of taxa known from the Marojejy massif in northeastern Madagascar. Following the key, descriptions of new species and notes on the circumscription of some previously published species are provided along with information on geographical distribution and citation of collections from Marojejy. Six of these (Weinmannia lowryana, W. integrifolia, W. marojejyensis, W. pauciflora, W. rakotomalzana, and W. venosa) are described as new and one new combination (W. arguta) is made. The species present at Marojejy are a broad sample of the diversity among Malagasy Weinmannia and contain members of both sections Inspersa and Spicata, as well as five of the seven species-groups that occur in Madagascar.