单齿玄参 dan chi xuan shen

Scrophularia duclouxii Stiefelhagen & Bonati; S. stiefelhagenii Bonati.

Herbs, to 1 m tall. Stems glandular, hairy or basally subglabrous, pith white. Leaves ca. 8-10 pairs; petiole to 2.5 cm, narrowly winged, glandular hairy or glabrous; leaf blade ovate to ovate-lanceolate, glabrous, puberulent, or pilose, base broadly cuneate, rounded, or subcordate, margin regularly to somewhat irregularly serrate or rarely double serrate. Thyrses narrow, ca. 20 cm; peduncle 0.5-1.5 cm, glandular hairy; bracts small. Pedicel 0.5-1.5 cm, glandular hairy. Calyx 2-3 mm; lobes ovate-lanceolate to lanceolate-oblong, apex obtuse to acute. Corolla 5-8 mm; tube 3-5 mm; upper lip 1-1.5 mm longer than lower lip; lobes orbicular, with overlapping margins, lateral lobes wider than long, middle lobe smaller than lateral lobes. Stamens as long as or slightly shorter than lower lobes; staminode small, subglobose, as wide as long. Ovary ca. 2 mm. Style ca. 2 mm. Capsule ovoid, 6-7 mm including beak. Fl. Jul-Aug, fr. Aug-Oct.

* Forests, grassland on mountain slopes, riverbanks; 1800-3800 m. SW to W Sichuan, S to SE Xizang, NW Yunnan.