Basionym: Scirpus mucronatus Linnaeus subsp. clemensii Kükenthal, Bot. Jahrb. Syst. 69: 259. 1938; Schoenoplectus fohaiensis (Tang & F. T. Wang) Hayasaka; S. mucronatus (Linnaeus) Pallas subsp. clemensii (Kükenthal) Soják; Scirpus clemensii (Kükenthal) Ohwi; S. fohaiensis Tang & F. T. Wang.
Rhizomes short, without creeping stolons. Culms 60-120 cm tall, 5-8 mm thick, terete, smooth, clothed at base with 3 or 4 leaf sheaths. Leaf sheaths brown to greenish, mouth obliquely truncate and bladeless or sometimes setaceous. Involucral bract 1, culmlike, 2.5-5 mm, often deflexed, terete, apex acuminate. Inflorescence a pseudolateral head with many spikelets. Spikelets sessile, dark brown, ovoid to oblong, 4-5 × ca. 3 mm, many flowered. Glumes pale brown with dark brown lines, obovate to elliptic, 2-2.5 mm, membranous, margin ciliolate, apex acute to obtuse with a costa excurrent into a mucro. Perianth bristles 5 or 6, as long as to slightly longer than nutlet, retrorsely scabrous. Stamens 3; anthers linear; connective apex evident beyond anthers. Style long; stigmas 2. Nutlet black at maturity, broadly obovoid to obovoid, ca. 1.2 mm, plano-convex, shiny. Fl. and fr. Mar-Jun.
Ponds; ca. 1600 m. Yunnan (Fuhai) [Papua New Guinea, Vietnam].