三脉山黧豆 san mai shan li dou

Orobus alatus Maximowicz, Prim. Fl. Amur. 83. 1859; Lathyrus alatus (Maximowicz) Komarov (1904), not Tenore (1811), nor Smith (1813); O. vernus Linnaeus var. alatus (Maximowicz) Regel.

Herbs perennial, 40-70 cm tall. Stem erect, rarely branched, glabrous, narrowly winged. Leaves aristate at apex; rachis narrowly winged; stipules semisagittate, 15-25 × 3-8(-12) mm, rarely dentate; leaflets (2 or)3-5-paired, narrowly ovate to oblanceolate, glabrous, with 3(-5) parallel veins raised abaxially and sunken adaxially, apex acuminate. Raceme shorter than leaf, 3-8-flowered; bracts membranous, persistent. Calyx campanulate, glabrous; longest tooth ca. 5 mm, equaling tube. Corolla purple, 13-18 mm; standard orbicular, with claw; wings shorter than standard, auriculate at base. Ovary linear, gla­brous. Legume black-brown, linear, 3.7-4.5 cm, glabrous. Seeds brown, subglobose, smooth. Fl. May-Jun, fr. Jun-Aug.

Forests, grasslands. Heilongjiang, Jilin, Nei Mongol [Korea, Rus­sia].