Carexduanensis (Carexsect.Rhomboidales), a new species of Cyperaceae from limestone areas of Guangxi, China.

Carexduanensis Z.C.Lu, Y.F.Lu & X.F.Jin, a new species in limestone areas of Guangxi, China, was discovered and described. The morphology showed that C.duanensis is similar to C.calcicola, but differs in having culms central, leaf blades 3-5.5 mm wide, bracts longer than spikes, utricles 4-5 mm long, shorter, and nutlets abruptly contracted into an erect beak at apex. SEM microphotographs of utricles and nutlets are provided for the new and related species, C.calcicola.