双穗雀稗Paspalum paspaloides (Michx.) Scribn.

科名：禾本科 Gramineae

属名：雀稗属 Paspalum

《中国植物志》第10(1)卷290页
  9. 双穗雀稗（华南经济禾草）图版89：6-11
  Paspalum paspaloides (Michx.) Scribn. in Mem. Torrey Bot. Club. 5: 29. 1894; Bor in Rech. f. Fl. Iran. 70: 494. 1970; Tzvel. in Fed. Poaceae URSS. 669. 1976; Clayt. in Tutin et al. Fl. Europ. 5: 263. 1980; Cope in Nasir, Fl. Pakist. 143: 211. 1982. ——Digitaria paspaloides Michx. Fl. Bor. Amer. 1:46. 1803. ——Paspalum distichum auct. non L.: Rendle in Journ. Linn. Soc. Bot. 36: 319. 1904; Hitchc. in Lingn. Sci. Journ. 7: 215. 1931, et Man. Grass. Unit. Stat. 603, f. 866.1951; Ohwi. Fl. Japon. 184. 1965;中国主要植物图说 禾本科638, 图634. 1959; Bor. Grass. Burm. Ceyl. Ind. Pakist. 338. 1960: 台湾的禾草581. 图185. 1975;中国高等植物图鉴5: 168, 图7165, 1976; 海南植物志4: 426. 1977: 台湾植物志5: 583. 1978.
  多年生。匍匐茎横走、粗壮，长达1米，向上直立部分高20-40厘米，节生柔毛。叶鞘短于节间，背部具脊，边缘或上部被柔毛；叶舌长2-3毫米，无毛；叶片披针形，长5-15厘米，宽3-7毫米，无毛。总状花序2枚对连，长2-6厘米；穗轴宽1.5-2毫米；小穗倒卵状长圆形，长约3毫米，顶端尖，疏生微柔毛；第一颖退化或微小；第二颖贴生柔毛，具明显的中脉；第一外稃具3-5脉，通常无毛，顶端尖；第二外稃草质，等长于小穗，黄绿色，顶端尖，被毛。染色体2n=40（Brown，1948），48（Burton, 1942），60（Gupta et al.，1974）。花果期5-9月。
  产江苏、台湾、湖北、湖南、云南、广西、海南等省区；生于田边路旁，曾作一优良牧草引种，但在局部地区为造成作物减产的恶性杂草。全世界热带、亚热带地区均有分布。

《Flora of China》 Vol. 22 (2006)
Paspalum distichum  Linnaeus
双穗雀稗   shuang sui que bai
Digitaria paspalodes Michaux; Paspalum paspalodes (Michaux) Scribner.
Perennial with rhizomes and stolons. Culms 20–50 cm tall, nodes usually pubescent. Leaf sheaths keeled, glabrous, margins ciliate; leaf blades linear, 5–10 × 0.3–0.7 cm, glabrous, apex acute; ligule 2–3 mm. Inflorescence of 2(–3) racemes arising together or separated by a short axis; racemes 3–7 cm; spikelets single, in 2 rows; rachis straplike, 1.5–2 mm wide. Spikelets pallid, obovate-oblong, plano-convex, 3–3.5 mm, acute; lower glume vestigial or a narrow triangular scale up to 1/2 spikelet length or more; upper glume papery, 3–5-veined with distinct middle vein, loosely appressed pubescent; lower lemma 3–5-veined, usually glabrous; upper lemma pale green, almost equal to spikelet, cartilaginous, apex apiculate and minutely pubescent. Fl. and fr. May–Sep. 2n = 40, 48, 60.
Fields, roadsides, ditches and other disturbed places, mostly on moist fertile soils. Anhui, Fujian, Guangxi, Guizhou, Hainan, Henan, Hong Kong, Hubei, Hunan, Jiangsu, Shandong, Sichuan, Taiwan, Yunnan, Zhejiang [tropical and warm-temperate regions of the world].
The length of the lower glume is very variable, even within a single raceme. The spikelets are not obviously hairy because the pubescent upper glume faces inward, but the creeping habit together with paired racemes of plump spikelets are distinctive. Rarely the upper glume is glabrous, but such specimens can be separated from the closely related Paspalum vaginatum by spikelet shape and by the longer, apiculate fertile floret.