Carex Paracheniana (carex Sect. Rhomboidales, Cyperaceae), a New Species from Guangxi and Guizhou, China

Carex paracheniana, a new species of Cyperaceae from China, is described and illustrated. The new species is recognized as a member of Carex sect. Rhomboidales in having broadly ovoid perigynia and rhombic-ovoid nutlets. It is similar to C. cheniana and C. brevicuspis, but differs from the former in having narrower leaves 3-5 mm wide, staminate scales that are obtuse at the apex, and nutlets abruptly contracted into a ca. 1 mm long, slightly curved beak at the apex. It differs from C. brevicuspis in having ovate-elliptic pistillate scales that are glaucous or pale yellow and long-awned at the apex, and styles that are thickened at the base. Micromorphological characters of the leaf epidermis, perigynia, and nutlets are compared among taxa.