日南薹草 ri nan tai cao

Rhizome short, without stolons. Culms slightly loosely tufted, ca. 70 cm tall, stiff, triquetrous, scabrid on upper part or smooth, 1- or 2-leaved. Leaves ± stiff, blades 2.5-4 mm wide, flat, sheaths at base dusky brown, usually not split. Involucral bracts long sheathed, lower involucral bract blades leaflike. Spikes numerous, 1-3 borne in an involucral bract sheath, androgynous, cylindric, 1.5-3 cm, loosely many flowered; peduncle slightly exserted or included in involucral bract sheath. Female glumes brownish, ovate-oblong, ca. 3.5 mm, thinly 1-costate, apex acute but muticous. Utricles brown, suberect, subequaling or slightly longer than glume, broadly ovate or elliptic, compressed biconvex, 3.5-4 mm, membranous, glabrous except scabrous on margins, several veined, base abruptly contracted into a short stipe, apex gradually narrowed to a medium-sized beak, orifice 2-toothed. Nutlets tightly enveloped, orbicular-ovate, compressed biconvex, ca. 2 mm; style strict and short, base thickened; stigmas 2, ± long.

Forests on mountain slopes. Jiangsu, Taiwan, Zhejiang [Japan].