24. Indigofera hamiltonii Graham ex Duthie & Prain, Ann. Roy. Bot. Gard. (Calcutta). 9: 22. 1901.
腾冲木蓝 teng chong mu lan
Indigofera tengyuehensis H. T. Tsai & T. T. Yu.
Shrubs. Stems yellowish gray, with appressed white medifixed 2-branched trichomes. Stipules narrowly lanceolate, ca. 3 mm, caducous. Leaves ca. 13 cm, mostly 3- or 5-foliolate, more rarely to 11(or 13)-foliolate; petiole and rachis with appressed medifixed trichomes; petiole 1.5-2 cm; rachis flattened and adaxially grooved; stipels subulate, minute; petiolules 1.5-2 mm, with appressed brown trichomes; leaflet blades opposite, elliptic-oblong, 1.2-2.2 × 0.7-1.2 cm, papery, both surfaces with appressed white medifixed trichomes, midvein adaxially impressed, secondary veins 5 or 6 on each side of midvein, base broadly cuneate to subrounded, apex rounded, truncate, or emarginate and mucronate. Racemes 15-20 cm, laxly flowered; peduncle 1.5-2 cm; bracts linear-lanceolate, ca. 2 mm, caducous. Pedicel 1-2 mm, deflexed in fruit, hairy. Calyx campanulate, ca. 3 mm, with appressed medifixed trichomes; tube ca. 1.5 mm; teeth triangular to ovate, most abaxial one as long as tube, margin densely ciliate, apex long acuminate. Corolla purple; standard elliptic-oblong, 10-12 × ca. 6 mm, outside glabrescent, base clawed, apex obtuse; wings and keel clawed at base; wings as long as keel. Stamens 5-8 mm; anthers ovoid, base with a few trichomes. Ovary glabrous, with 6-8 ovules. Legume linear, cylindric, ca. 3.5 cm, glabrescent. Fl. and fr. May.
Forests on slopes; ca. 1000 m. W Yunnan [India].
Sanjappa (Bull. Bot. Surv. India 21: 73. 1995) reported the leaves of this species as 3- or 5(-13)-foliolate.
Although the protologue of Indigofera tengyuehensis is not a good match for I. hamiltonii as currently understood, examination of isotype material (E!) shows that it obviously belongs here. We have not found the holotype specimen; its leaves were described as 9-15-foliolate in the protologue, but they are only 3-7-foliolate in the examined isotype.