别名：sweet signalgrass;

科名：禾本科 Gramineae

属名：臂形草属 Brachiaria

《中国植物志》第10(1)卷269页
  6.臂形草（禾本科图说）图版81：8-10
  Brachiaria eruciformis (J. E. Smith) Griseb. in Ledeb. Fl. Ross. 4: 469. 1853; Hand. -Mazz. Sym. Sin. 7: 1303. 1936; 中国主要植物图说 禾本科678. 图620. 1959; Bor, Grass. Burm. Ceyl. Ind. Pakist. 283. 1960; 中国高等植物图鉴5: 863. 1976.——Panicum eruciforme J. E. Smith in Sibth. et J. E. Smith, Fl. Graeca 1: 44, t. 59. 1806.——Panicum isachne Roth. ex Roem. et Schult. Syst. Veg. 2: 458. 1817. ——Panicum caucasicum Trin. in Mom Acad. Sci Ntersb. Ser 6(3): 237. 1834.——Echsnochloa eruciformis (J. E. Smith) Koch in Linnaea 21: 437. 1848. ——Brachiaria isachne (Roth. ex Roem. ) Stapf in Prain, Fl. Trop. Afr. 9: 552. 1919.
  一年生草本，高30-40厘米。秆纤细，基部倾斜，节上生根，多分枝，节带具白柔毛。叶鞘无毛或鞘缘疏生疣毛；叶舌退化呈一圈白色繸毛；叶片线状披针形，扁平，内卷，长1.5-10.5厘米，宽3-6毫米，边缘齿状粗糙，密生脱落性细毛。圆锥花序由4-5枚总状花序组成，总状花序长5-12厘米；穗轴被纤毛，棱边粗糙；小穗卵形，长约2毫米，被纤毛，具长约0.2毫米的柄；第一颖长0.2-0.3毫米，膜质，无毛，顶端下凹；第二颖与小穗等长，具5脉，第一外稃与第二颖同形，具5脉，内稃狭窄；第二外稃长圆形，坚硬，光滑，长约1.5毫米，边缘稍内卷，包着同质的内稃。染色体2n=18（Delay, 1954）。
  产贵州、福建、云南；生于山坡草地或旱田中。分布于地中海，经非洲北部至印度。模式标本采自希腊。

《Flora of China》 Vol. 22 (2006)
Brachiaria eruciformis  (Smith) Grisebach
臂形草   bi xing cao
Panicum eruciforme Smith in Sibthorp & Smith, Fl. Graeca 1: 44, t. 59. 1806; Brachiaria isachne (Roth ex Roemer & Schultes) Stapf; Echinochloa eruciformis (Smith) Koch; Moorochloa eruciformis (Smith) Veldkamp; P. caucasicum Trinius; P. isachne Roth ex Roemer & Schultes.
Annual. Culms loosely tufted, slender, much branched, geniculately ascending, 30–40 cm tall, nodes softly hairy. Leaf sheaths glabrous or loosely tuberculate-hairy; leaf blades linear-lanceolate, 1.5–10.5 × 0.3–0.6 cm, glabrous or pilose; ligule ciliate. Inflorescence axis 3–6 cm; racemes 4–10, 1–3 cm, erect or narrowly ascending; rachis narrow, triquetrous, ciliate or scabrous; spikelets single, in 2 rows, overlapping. Spikelets elliptic, 1.8–3 mm, pilose, subacute; lower glume 0.2–0.3 mm, membranous, glabrous; upper glume and lower lemma as long as spikelet, 5-veined; upper floret readily deciduous, oblong, ca. 1.5 mm, thinly crustaceous, smooth, glossy, apex obtuse. Fl. and fr. summer–autumn. 2n = 18.
Open and disturbed situations on hill slopes and in dry fields as an arable weed. Fujian, Guizhou, Yunnan [India, Malaysia, Thailand; N Africa, Mediterranean region].
This is the only species of Brachiaria occurring in China with a fertile floret which is shed from the mature spikelet. The fertile floret is also distinctive due to its smooth, glossy texture and obtuse apex.

This species and two close relatives in Africa have been placed in the separate genus Moorochloa Veldkamp.

【拼音名】 Bì Xínɡ Cǎo
【来源】 药材基源：为禾臂本科植物毛臂形草的全草。
拉丁植物动物矿物名：Brachiaria villosa（Lam.）A.Camus
采收和储藏：夏、秋季采收，鲜用或晒干。
【原形态】 毛臂形草 一年生草本。须根细弱。秆高10-40cm，基部倾斜，全株密被柔毛，尤以鞘口及边缘更密。叶舌短小，具长约lmm的纤毛；叶片卵状被针形，长1-4cm，宽3-10mm，两面密被柔毛，先端急尖，边缘呈波状皱折，基部钝圆。圆锥花序由4-8枚总状花序组成；总状花序长1-3cm；主轴与穗轴密被柔毛；小穗卵形，先端尖，长约2.5mm，被短柔毛或几无毛，小穗柄长0.5-1mm，有毛；第1颖长为小穗之半，具3脉，背部对向穗轴，第2颖略短于小穗，具5脉；第1外稃等长于小穗，具5脉，内稃膜质，狭窄，第2外稃革质，稍包卷内稃，具横细皱纹；鳞被2.膜质，折叠；花柱基分离。谷粒椭圆形，长约2mm。花、果期7-10月。
【生境分布】 生态环境：生于田野和山坡草地。
资源分布：分布于陕西、甘肃、安徽、浙江、江西、福建、台湾、河南、湖北、湖南、广东、广西、四川、贵州、云南等地。
【性味】 甘、淡；微寒
【功能主治】 清热利尿；通便。主小便赤涩；大便秘结
【用法用量】 内服:煎汤，15-30g；鲜品30-90g。
【摘录】 《中华本草》