123. Strobilanthes tenax Dunn, Bull. Misc. Inform. Kew. 1920: 209. 1920.
结壮马蓝 jie zhuang ma lan
Subshrubs to 1 m tall. Stems 4-angled, sulcate, gland-tipped pubescent. Petiole 2-5 mm but apical leaves sessile; leaf blade lanceolate, 8-10 × 2.5-4 cm, glabrous, cystoliths numerous, linear, and prominent, secondary veins 4-6 on each side of midvein, base cuneate, margin serrate, apex acuminate. Inflorescences terminal, a panicle of branched spikes, 3-12 cm; rachis gland-tipped pilose; sterile bracts sessile, leaflike, oblong-lanceolate to ovate, 8-12 × 3-5 mm; floral bracts oblong-elliptic, 5-7 × ca. 2 mm, scarious and early caducous, sparsely gland-tipped pilose, apex obtuse; bracteoles apparently absent. Flowers sessile, with opposite pairs 1-2.5 cm apart on rachis. Calyx ca. 1 cm, outside gland-tipped pubescent, 5-lobed almost to base; lobes linear, apex acute. Corolla color unknown, ca. 3 cm, straight, outside glabrous, inside glabrous except for trichomes retaining style; tube basally cylindric and 1-2 mm wide for ca. 0.8 cm then abruptly widened to ca. 1 cm at mouth; lobes broadly ovate, 5-6 × ca. 3 mm, apex rounded. Stamens 4, included; filaments glabrous, shorter pair 1-2 mm, longer pair 3-4 mm; anther thecae obliquely ellipsoid, ca. 1.5 mm, incurved; pollen type 3. Ovary obovoid, ca. 2.5 mm, gland-tipped with a few apical trichomes; style ca. 1.9 cm, thinly pilose. Capsule narrowly obovoid, ca. 1.5 cm, gland-tipped pubescent, 4-seeded. Seeds immature. Fl. Mar.
● Forests; ca. 800 m. Xizang (Mêdog).
Strobilanthes tenax is only known from the type, and there are many errors in the protologue.