美脉木蓝 mei mai mu lan

Indigofera oblonga Craib.

Shrubs, erect. Branches angular, with dense appressed brown subbasifixed asymmetrically 2-branched trichomes. Stip­ules narrowly triangular, 4-5 mm. Leaves simple or 1-foliolate; petioles 1-1.5 cm; stipels linear-subulate, 1.5-2 mm; leaflet blade oblong to elliptic, 8-10 × 4-5.5 cm, thickly papery, abaxi­ally with gray and spreading to subspreading gray or brown subbasifixed extremely asymmetrically 2-branched trichomes, adaxially dark green and glabrous, secondary veins 15-17 on each side of midvein and conspicuous, base broadly cuneate to rounded, apex obtuse to rounded. Racemes 7-13 cm; peduncle short; bracts linear-setaceous, 3.5-4 mm, caducous. Pedicel 3-5 mm in fruit, densely tomentose. Calyx 2-2.5 mm, with densely ascending subbasifixed trichomes; teeth triangular. Corolla pink; standard ovate, 8-10 mm, outside densely appressed brown pu­bescent, apex obtuse and mucronate; wings 6-8 mm, margin ciliate; keel outside densely appressed brown pubescent. Sta­mens 8-10 mm; anthers hairy at base. Ovary glabrous or sparsely strigose. Legume cylindric, 4-5.3 cm, with small ap­pressed trichomes; endocarp red blotched. Seeds 8-11 per leg­ume, dark brown. Fl. unknown for China, fr. Nov-Dec.

Moist places near rivers; ca. 900 m. S Yunnan [India, Laos, Myan­mar, Thailand, Vietnam].

This species was described by Kurz as having pink flowers and a densely silky pubescent ovary; however, Sanjappa (Reinwardtia 10: 218-219. 1985) described it as having a glabrous ovary, and de Kort and G. Thijsse (Blumea 30: 112. 1984) described it as having whitish and yellow flowers and a strigose ovary. The Chinese specimens are without flowers. Two specimens from Thailand were recorded as flowering "pinkish" (Kerr no. 5171, K!) and "yellow-white" (K. Larsen et al. no. 1912, K!), respectively.