Description

Key Characters:

Growth Form: Tufted perennials with short, woody rhizomes.

Stems: Culms trigonous, 100–150 cm tall, smooth or weakly scabrous on angles below inflorescence.

Roots: Fibrous root system.

Leaves: Leaves simple. 3-ranked. Blades linear, plicate, shorter than to as long as the culm, 6–13 mm wide. Apex gradually tapering and long-acuminate. Margins entire. Sheathing; sheaths reddish brown, with chestnut brown, hyaline ventral side split into parallel fibers; cataphylls brown to purplish brown, ventrally split into dark brown fibers. Stipules absent.

Flowers: Flowers in spikes 6–9, subdigitate near apex of culm, the terminal spike purplish brown, staminate, cylindrical,2–6 cm long, usually shorter than lateral spikes, the lateral spikes androgynous with a short, staminate, apical part, cylindrical, 6–15 cm long, 3–6 mm wide, moderately open, sometimes exposing rachilla internodes between the flowers, subsessile or the lowest one with a short peduncle, ascending; bracts 3–4, elongated, lower 1–2 much longer than the inflorescence, not sheathing; pistillate glumes dark purplish brown, membranous to chartaceous, elliptic or ovate, 4–5 mm long, 1.5–2 mm wide, 3–nerved, the midnerve yellowish, prolonged into a serrulate–scabrous awn 1.5–2 mm long; perigynium subcoriaceous, dark purplish brown or blackish purple, glossy, ellipsoid to obovoid–ellipsoid, 3.5–6.5 mm long, 1.5–2 mm wide, glabrous, inconspicuously 2–nerved, abruptly narrowed to a short beak, the orifice bidentate and usually spinulose. Flowers unisexual. Corolla (petals) absent. Ovary superior; stigmas 2.

Fruit: Achenes broadly obovoid; lenticular. Seeds 1; seed coat thin; free from pericarp; embryo basal; endosperm abundant.

Ploidy:

Habitat: Occurring in open sites in wet forest.

Elevation Range: 1065–1225 m.