凹脉马兜铃 ao mai ma dou ling

Herbs twining. Stems 6-angled, pubescent. Petiole 1.5-2 cm, glabrate; leaf blade ovate-lanceolate to lanceolate, 8-20 × 4-5 cm, subleathery, abaxially densely pubescent along veinlets, adaxially glabrous, veins palmate, 1-2 pairs from base, base auriculate, sinus 0.4-0.6 cm deep, apex acuminate. Racemes in axils of leafy shoots, 3-7-flowered, 1-4 cm. Pedicel ascending, ca. 1.5 cm, sparsely hairy, glabrescent; bractlets lanceolate, ca. 10 × 3 mm. Calyx pale yellowish or greenish, throat purple, 2.5-3 cm; tube rectilinear or slightly curved; utricle globose, ca. 4 mm in diam., with stipe 2-3 mm; tube 5-10 × 1.5-2 mm; limb ligulate, elliptic, 2-2.5 × 0.5-1 cm, apex obtuse. Anthers ovoid, 3-4 mm. Gynostemium 6-lobed. Capsule obovoid to subglobose, ca. 1.7 × 1.3 cm, dehiscing acropetally. Seeds cordiform to deltoid, 2.5 × 2.5 mm. Fl. May-Jun, fr. Aug-Oct.

* Forests, thickets, limestone mountain slopes; ca. 400 m. Guangxi.

The specific epithet was spelled “impressinervia” on p. 15 of the protologue and “impressinervis” on pp. 11, 12, and [26].

This species is used medicinally.