椭圆叶木蓝 tuo yuan ye mu lan

Indigofera arborea Roxburgh; I. elliptica Roxburgh; I. leptostachya Candolle; I. pulchella Roxburgh; I. violacea Roxburgh.

Shrubs, 1-1.5 m tall. Stems brown, robust, with obvious lenticels; young branches green or red-brown, angular, with ap­pressed white medifixed symmetrically 2-branched trichomes. Stipules linear, caducous. Leaves 5.5-15 cm, 13-21-foliolate; petiole and rachis with sparse appressed medifixed trichomes; petiole 1.1-1.8 cm; rachis adaxially grooved; stipels subulate, ca. 1 mm; petiolules ca. 2 mm, hairy; leaflet blades opposite, subopposite, or rarely alternate, elliptic to obovate, 1-2.4 × 0.7-1.5 cm, both surfaces with appressed white medifixed tri­chomes, midvein abaxially prominent and adaxially slightly impressed, secondary veins 8-11 on each side of midvein and obvious, base cuneate to rounded, apex obtuse to truncate. Ra­cemes 4-17 cm; peduncle very short, base with persistent bud scales; rachis angular, with appressed brown trichomes; bracts ovate to lanceolate, 2-4 mm, caducous, abaxially with ap­pressed brown to grayish brown trichomes. Pedicel 1-2 mm, hairy. Calyx cup-shaped, 2.5-3.5 mm, outside with sparse ap­pressed white trichomes; teeth triangular, as long as tube. Co­rolla purple to light purple; standard broadly ovate, ca. 10 × 7-7.5 mm, glabrous, base clawed, apex obtuse; wings 8-9.5 mm, base auriculate and clawed, margin ciliate; keel 9-9.5 mm, out­side apically hairy, very shortly spurred, margin ciliate. Stamens 7-9.5 mm; anthers ovoid to ellipsoid, glabrous. Ovary glabrous. Legume cylindric, 2.4-4.5 cm × ca. 4 mm, glabrous; endocarp blotched. Seeds 8-12 per legume, reddish brown, cubic, ca. 2 × 2 mm. Fl. Jan-Mar, fr. Apr-Jun. 2n = 16.

Slopes, grasslands, sparse woodlands, scrub; 300-2000 m. W Guangxi, Yunnan [Bhutan, India, Laos, Myanmar, Nepal, Pakistan, Sri Lanka, Thailand, Vietnam].