三叶马先蒿 san ye ma xian hao

Herbs perennial, 30--50 cm tall, pubescent, drying ± black. Rootstock stout, fleshy. Stems often several, erect or ± curved. Basal leaves in a rosette; petiole to 7 cm, glabrous; leaf blade ± lanceolate, to 9 cm, glabrous on both surfaces, pinnatipartite to pinnatisect; segments to 14 pairs, incised-dentate. Stem leaves in 2 or 3 or 4 whorls, smaller than basal leaves; petiole 1--1.6 cm. Flowers laxly arranged in spikes, only 1--3 whorls, grayish tomentose; bracts leaflike, proximal ones longer than flowers, sparsely pubescent. Calyx arachnoid; lobes 5, unequal, posterior lobe smallest, all oblong-triangular, entire. Corolla violet, small; tube slightly longer than calyx, bent forward apically near calyx lobes; galea truncate at apex; lower lip ca. as long as galea. Filaments glabrous. Capsule compressed, ovoid, to 2 X 1 cm, apex acute. Seeds to 3.5 mm. Fl. Jul, fr. Jul--Aug.

* Thickets; 3200--4600 m. W Gansu, Nei Mongol, Qinghai.