Dracocephalum isabellae Forrest ex W. W. Sm.

This is the largest-flowered species in the group of pinnatisect-leaved species.

Herbs perennial. Stems erect, 30-50 cm, angles retrorse pubescent, nodes numerous, internodes 3-4 cm. Leaves pinnatisect, subsessile, with a short sheath basally, broadly ovate to rhombic-ovate, 2-2.8 × 2.6-3.8 cm, adaxially glabrous, abaxially sparsely pubescent on veins; segments in 2 or 3 pairs, crowded at midrib base, obliquely spreading at an obtuse angle, linear to oblanceolate-linear, 1.3-2 cm × 1-2.1 mm, middle lobe 1.7-2.4 cm, margin ciliate, revolute when dry, apex obtuse. Verticillasters 4-flowered, inserted on upper 3 stem nodes, loose; bracts obovate, 0.8-1.2 cm, base cuneate, tripartite; sections lanceolate, densely lanate-ciliate, apex acute. Calyx 1.5-2 cm, 2-lipped 1/5-1/4 its length, densely lanate-villous, margin densely ciliate; upper lip teeth divisions to 1.2 cm; teeth equal, ovate-lanceolate, apex subulate-acuminate; lower lip 2-toothed to lip base, teeth lanceolate-triangular. Corolla blue-purple, 3.5-4.2 cm, pubescent. Fl. Jul-Aug.

Yunnan (Zhongdian Xian)

* Rocky grasslands among forests; 3000-4000 m.