Piper jianfenglingense, a new species of Piperaceae from Hainan Island, China

Piper jianfenglingense, which was collected in the Jianfengling National Natural Reserve, Hainan Island, China, is described and illustrated herein. Morphologically it is similar to P. mutabile, from which it differs in having sparsely pubescent petioles, vaginate at base only; rachises glabrous; floral bracts adnate to rachis, margin partially hidden; stamens 2, with considerably longer filaments, these caducous when anthers mature; stigmas ovoid, apex acute; berries and seeds ellipsoid. Molecular analyses based on the ITS marker of nuclear ribosomal DNA strongly support P. jianfenglingense as a new species in the genus Piper, most closely related to P. macropodum.