54. Cyperus cyperoides (Linnaeus) Kuntze, Revis. Gen. Pl. 3: 333. 1898.
砖子苗 zhuan zi miao
Scirpus cyperoides Linnaeus, Mant. Pl. Alt. 181. 1771; Cyperus cyperoides var. microstachys Kükenthal; C. cyperoides var. subcompositus (C. B. Clarke) Kükenthal; C. subumbellatus Kükenthal; C. umbellatus Bentham, nom. illeg. superfl.; Kyllinga sumatrensis Retzius; K. umbellata Rottbøll, nom. illeg. superfl.; Mariscus cyperoides (Linnaeus) Urban (1900), not (Roxburgh) A. Dietrich (1832); M. philippensis Steudel; M. sieberianus Nees ex C. B. Clarke; M. sieberianus var. evolutior C. B. Clarke; M. sieberianus var. khasianus C. B. Clarke; M. sieberianus var. subcompositus C. B. Clarke; M. sumatrensis (Retzius) J. Raynal; M. sumatrensis var. evolutior (C. B. Clarke) C. Y. Wu ex Karthikeyan; M. sumatrensis var. khasianus (C. B. Clarke) C. Y. Wu ex Karthikeyan; M. sumatrensis var. microstachys (Kükenthal) L. K. Dai; M. sumatrensis var. subcompositus (C. B. Clarke) Karthikeyan; M. umbellatus Vahl, nom. illeg. superfl.; M. umbellatus var. evolutior (C. B. Clarke) E. G. Camus; M. umbellatus var. microstachys (Kükenthal) Tang & F. T. Wang; M. umbellatus var. sieberianus (Nees ex C. B. Clarke) E. G. Camus; M. umbellatus var. subcompositus (C. B. Clarke) Tang & F. T. Wang.
Perennials. Rhizomes short, hardened. Culms laxly tufted, 10-60 cm tall, acutely triquetrous, smooth, base swollen and with more leaves. Leaves shorter than to equaling culm; sheath brown to reddish brown; leaf blade 3-6(-8) mm wide, folded at basal part but apically gradually flattened, margin not scabrous. Involucral bracts 5-8, obliquely spreading, leaflike, longer than inflorescence. Inflorescence a simple or subcompound anthela; rays several, 6-12 or sometimes more, short or 6-14 cm, unequal in length, each with 1-5 spikes. Spikes cylindric, 1-2.5[-5] cm × 5-10 mm or sometimes narrower, with many dense spikelets. Spikelets narrowly linear-ovoid, 3-7 × ca. 0.7 mm or sometimes shorter, spreading to reflexed, each (1 or)2- or 3-flowered; rachilla wings white, lanceolate, broad, hyaline. Glumes yellow, yellowish green, or greenish, oblong, ca. 3 mm, veins several with middle 3 green and conspicuous, margin involute, apex obtuse and not mucronate. Stamens 3; anthers broadly linear, 0.8-1 mm; connective prominent beyond anthers. Style short; stigmas 3, slender. Nutlet straw-colored at first but dark brown when mature, narrowly oblong, 1.8-2.2 × ca. 0.5 mm, ca. 2/3 as long as subtending glume, 3-sided, minutely punctate. Fl. and fr. Apr-Dec. 2n = 82, 88, 134, 220, 224.
Sunny places on mountain slopes, grasslands along trails, ditch margins, river margins, wet places, forests, among herbs, sometimes in dry places; 100-1000(-3200) m. Anhui, Chongqing, Fujian, S Gansu, Guangdong, Guangxi, Guizhou, Hainan, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Sichuan, Taiwan, Xisha Qundao, Xizang, Yunnan, Zhejiang [Bhutan, India, Indonesia, Japan, Kashmir, Korea, Laos, Malaysia, Myanmar, Nepal, Pakistan, Papua New Guinea, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa, Atlantic Ocean islands, N Australia, Indian Ocean islands, Madagascar, Pacific islands].
Cyperus cyperoides is naturalized in tropical America.
This widespread species occurs nearly throughout the tropical and warm-temperate regions of the Old World. Numerous varieties have been recognized in China, which may be identical with subspecies and varieties named in Africa (e.g., R. W. Haines & Lye, Sedges & Rushes E. Afr. 204-206. 1983) and S Asia (Karthikeyan, Fl. Ind. Enumerat. Monocot. 64. 1989). Such varieties were based on differences in ray and bract length, number of spikes per ray, and number of fertile glumes per spikelet. Intergradations have been noted by Haines and Lye (q.v.) and characterize some specimens from S China and SE Asia. D. A. Simpson and T. Koyama (Fl. Thailand 6(4): 382. 1998) noted variability in this species (as well as the following species) and recognized no infraspecific taxa. We follow their broad concept for this species and for C. cyperinus.