Ophiorrhiza wulingensis, a new species of Ophiorrhizeae (Rubiaceae) from northwestern Hunan, China

Ophiorrhiza wulingensis, a new species of Rubiaceae from northwestern Hunan, China, is described and illustrated. The new species is similar to Ophiorrhiza chinensis and Ophiorrhiza howii, but it can be easily distinguished from the latter two by its hirtellous abaxial and glabrous adaxial leaf surfaces, dark-red hypanthia, shorter corolla tubes that are longitudinally ribbed abaxially and hooked near the apex, and densely pilose inside the corolla lobes. We preliminarily assessed it as Least Concern (LC) according to the IUCN Red List Categories and Criteria, as it faces no obvious threats and is often encountered as a dominant component in the herb layers.