3. Scleria tonkinensis C. B. Clarke, Bull. Misc. Inform. Kew, Addit. Ser. 8: 57. 1908.
越南珍珠茅 yue nan zhen zhu mao
Scleria kwangtungensis Chun & F. C. How; S. levis Retzius var. scaberrima Bentham.
Perennials. Rhizomes short, thick, woody, creeping, densely covered with scales; scale brown, tubular, with several parallel veins. Culms 16-70 cm tall, thinner, sharply 3-angled, villous at apical part. Leaves basal and cauline. Basal leaves only with closed sheath, without leaf blade; sheath pale brown, 3-angled, edges villous, surfaces pubescent, not winged, apex with 3 triangular teeth. Cauline leaves with a sheath like that of basal leaves; contraligule dark reddish brown, narrowly triangular, membranous; leaf blade linear, 0.5-1.5 cm wide but apically attenuate, both surfaces villous, margins scabrous, apex obtuse. Involucral bracts leaflike, basalmost to 5 cm, sheathing; bractlets setaceous, both surfaces villous. Inflorescences paniculate, 2.5-6 cm. Spikelets narrowly ovoid, 8-10 mm, villous, both bisexual and unisexual spikelets numerous, with 14-16 glumes. Glumes pale brown to yellowish green, basal 1 or 2 empty, 1 above empty ones with a female flower, others with male flowers. Male flowers: stamens 3. Female flower: style slender; stigmas 3, longer than style, slightly puberulent. Disk brown, stalklike, not lobed. Nutlet white, broadly obovoid to subspherical, 3-3.5 mm, obscurely 3-sided, obscurely rugose to subsmooth, shiny, apex rounded with a fine tip. Fl. and fr. Apr-Jul.
Moist grasslands, thickets; below 100 m. Guangdong, Guangxi, Hainan [Cambodia, Thailand, Vietnam].
Scleria tonkinensis was misidentified as S. radula by Tang and F. T. Wang (Fl. Reipubl. Popularis Sin. 11: 206. 1961).