泸西柴胡 lu xi chai hu

Plants 55–125 cm, stout, perennial. Taproot dark brown, thick, woody, little-branched, densely marked with annular leaf scars. Stem usually tinged purple at base, base without fibrous remnant sheaths. Basal leaves caespitose, lanceolate, 10–20 × 1.6–3 cm, abaxially glaucescent, 5–7-nerved, base tapering into long petiole, margins usually reddish-brown. Cauline leaves narrow-lanceolate, 8–18 × 1.2–2.5 cm, petiolate, clasping, 7–9-nerved. Apical leaves sessile, obovate, clasping, 9–11-nerved. Inflorescence profusely dichotomously branched forming a large panicle, branches spreading and rigid; umbels 2.5–4 cm across; bracts 5, obovate, 4–7 × 3–4 mm, unequal; rays 2–9, 1–4 cm; bracteoles 5, elliptic or obovate, ca. 3 × 2.5 mm, green, exceeding flowers; umbellules ca. 10 mm across, 8–17-flowered; pedicels 0.5–1 mm. Petals yellow. Stylopodium low-conic, discoid, yellow. Fruit oblong, brown, 2–3.5 × 1–2 mm; ribs prominent; vittae 3 in each furrow, 4 on commissure. Fl. and fr. Jul–Oct.

Mountain slopes; ca. 1800 m. SE Yunnan (Jianshui, Luxi).

The roots are used in traditional Chinese medicine. This rather poorly known taxon is recorded only from a few collections.