爱氏马先蒿 ai shi ma xian hao

Herbs perennial, less than 15 cm tall, drying black. Roots few, fascicled, ± fleshy. Stems many branched; branches diffuse basally. Leaves opposite; petiole to 4.5 cm; leaf blade linear-oblong to elliptic-oblong, to 5 X 2 cm, pinnatisect; segments 2--4 pairs, pinnatisect, dentate. Flowers axillary. Pedicel ca. 8 mm, sparsely long pubescent. Calyx ca. 1 cm, slightly cleft anteriorly; lobes 5, unequal, posterior tooth one linear and entire, lateral lobes larger, ovate, serrate. Corolla light purple with whitish purple tube; tube to 2.5 cm, slender, glabrous; galea bent at a right angle apically; beak straight, ca. 3.5 mm; lower lip not ciliate, middle lobe rounded, not hoodlike. 2 filaments pubescent, 2 glabrous. Fl. Jun.

* Riversides, damp places; ca. 4000 m. E Xizang.