Manipulus Rubiacearum IV. Kerianthera (Rubiaceae), a new genus from Amazonian Brazil

A new genus,Kerianthera, and its single new species,K. preclara, are presented.Kerianthera is a member of tribe Condamineeae and is easily distinguished from related genera by its 4-merous calyx, 7 or 8-merous corolla, stamens separating from the corolla tube at its apex, anthers with approximately 300 locelli, septicidal capsules, and seeds irregularly biwinged. It is most similar phenetically to the genusPinckneya with which it shares foliar calyx lobes on some flowers, corolla lobes densely pubescent on the inner surface, and winged seeds.