台北飘拂草 tai bei piao fu cao

Fimbristylis autumnalis (Linnaeus) Roemer & Schultes subsp. taiwanica (Ohwi) T. Koyama; F. taiwanica Ohwi.

Annuals. Culms densely tufted, 10-30 cm tall, 0.7-1.3 mm thick, flatly 3-angled, smooth. Leaves basal, few; sheath light straw-colored to pale brown; ligule ciliate; leaf blade linear, to 18 cm × 1.5-5 mm, flat, apical margin scabrid. Involucral bracts 3 or 4, basalmost leaflike and to 4 cm. Inflorescence a decompound anthela, 3-6 × 3-6 cm, lax; primary rays 2-5, 1-5 cm, unequal, apically scabrous. Spikelets numerous per inflorescence, solitary, rust-colored, narrowly ovoid, 2-3 × 1-1.2 mm, slightly angular, sublaxly 5-10-flowered, apex acute. Glumes numerous, spirally imbricate, light rust-colored with pale brownish margins, ovate, 1-2 mm, membranous, 3-veined forming an abaxial keel, apex mucronate. Stamens 1 or 2; anthers 0.2-0.3 mm. Style 3-sided, glabrous, basally dilated; stigmas 3. Nutlet subsessile, light straw-colored, obovoid, 0.4-0.5 × 0.3-0.4 mm, ± smooth or with scattered verrucae and slightly cancellate with transversely oblong cells.

Open wet places. Taiwan [India, Indonesia, Kashmir, Papua New Guinea, Philippines, Vietnam; Africa, Australia].