双萼马蓝 shuang e ma lan

Subshrubs 50-100 cm tall, isophyllous. Stems terete, glabrous. Petiole 0.7-1.5 cm, sparsely brown pilose; leaf blade elliptic, 6-22 × 3.5-10 cm, hirsute especially along veins, abaxially cystoliths prominent, secondary veins 12-16 on each side of midvein, base cuneate, margin remotely serrate, apex acute. Inflorescences axillary or terminal, abbreviated to headlike spikes, ca. 2 cm; peduncle 2-4 mm, brown pubescent; bracts ovate, 3-3.5 × 1.2-1.7 cm, glabrous except for ciliate margin, margin entire or apically serrate, apex acute; bracteoles oblong-lanceolate, ca. 15 × 3 mm, glabrous. Calyx with appressed silky trichomes on both surfaces, 2-lipped; lower lip ca. 1.2 cm, 2-lobed, lobes triangular and ca. 1.5 × 1.5 mm; upper lip ca. 1.3 cm, 3-dentate to ca. 1 mm. Corolla purplish blue, ca. 4 cm, ventricose, outside glabrous, inside glabrous except for trichomes retaining style; tube basally cylindric and ca. 2 mm wide for ca. 1.2 cm then gradually widened to ca. 1.4 cm at mouth; lobes ovate, ca. 5 × 7 mm, apex obtuse. Stamens 4, included; shorter filament pair ca. 2 mm, glabrous; longer filament pair ca. 4.5 mm, sparsely pilose; anther thecae oblong, ca. 3 × 1 mm. Ovary glabrous; style ca. 3.2 cm, pilose. Capsule not seen. Fl. Dec.

Thickets on limestone hills; 300-900 m. Yunnan (Jinghong) [Laos].