烟豆 yan dou

Kennedya tabacina Labille, Sert. Austro-Caledon. 70. 1824; Glycine koidzumii Ohwi; G. membranacea Ohwi; G. pescadrensis Hayata; G. tabacina var. uncinata Bentham; Leptocyamus elongatus (Bentham) Bentham; Leptolobium elongatum Bentham; L. tabacinum (Labille) Bentham.

Herbs perennial. Stems slender, procumbent, usually curved, many branched at base, nodes obvious, sparsely pubes­cent. Leaves pinnately 3-foliolate; stipules lanceolate, ca. 2 mm, villous; petiole 2-3 cm, sparsely strigose; stipels linear, ca. 1 mm, hairy; leaflets at lower part of stem obovate or ovate to oblong, 0.7-1.2 × 0.4-0.8 cm, both surfaces adpressed white villous, denser abaxially, lateral veins 5-7 pairs, curved, reticu­late veins visible, base rounded, apex obtusely rounded, trun­cate or slightly emarginate, mucronate; leaflets at upper part of stem ovate-lanceolate, narrowly elliptic-oblong, or linear, 1.2-3.2 cm × 5-8 mm. Raceme slender and spreading, 1-5.5 cm; peduncle 3-7.5 cm; bracts linear, villous; flowers sparse, usu­ally 1 per bract or 2 or 3 clustered at lower part of rachis. Flow­ers 7-9 mm; pedicel ca. 2 mm; bracteoles slender. Calyx mem­branous, campanulate, densely strigose; lobes 5, triangular, longer than tube, upper 2 connate to middle. Corolla purple or light purple; standard orbicular, ca. 15 mm in diam., with claw; wings and keels smaller, with auricles and claws. Ovary with short stipe, many ovuled. Legume oblong, straight, not con­stricted between seeds, 20-25 × ca. 2 mm, adpressed white villous, stipe short, apex with beak ca. 2 mm. Seeds 2-5, dark brown, cylindric, truncate at 2 ends, ca. 2.5 × 2 mm; testa not shiny, with granular small nodules. Fl. Mar-Jul, fr. May-Oct. 2n = 40, 80.

Fujian, Guangdong, Taiwan [Japan; Australia, Oceania].

The Chinese record of Glycine clandestina J. C. Wendland (FRPS 41: 239. 1995) is based on a misidentification, probably of G. tabacina. True G. clandestina is endemic to Australia.