西藏马蓝 xi zang ma lan

Pteracanthus tibeticus (J. R. I. Wood) C. Y. Wu & C. C. Hu.

Subshrubs to 1.5 m tall, gregarious, probably pliestesial, nearly isophyllous. Stems slightly 4-angled, glabrous or obscurely bifariously pubescent. Petiole 1-3 cm, sparsely pilose; leaf blade ovate to elliptic, 7-14 × 3-9 cm, abaxially paler and subglabrous except for a few trichomes near base of midvein, adaxially green, subglabrous except for a few scattered short hispid trichomes, strigose or scurfy along midvein, and with conspicuous cystoliths, secondary veins 5 or 6 on each side of midvein, base narrowly cuneate and decurrent nearly to petiole base, margin strongly serrate, apex shortly acuminate and slightly falcate. Inflorescences axillary, spikes, 4-12 cm, secund, sometimes reduced to single axillary flowers; rachis finely puberulent to gland-tipped pilose, straight or obscurely zigzag, winged, wings 0.2-1 mm wide; bracts glabrous; basal bracts leaflike, with a petiole to 4 mm, ovate, 1.5-2.5 cm, apex acuminate; apical bracts sessile, narrowly oblong-elliptic, 1-1.2 cm, apex acuminate; bracteoles oblong, 2.5-4 mm, apex obtuse. Flowers to 1.5 cm apart on rachis. Calyx 0.9-2 cm, apparently not accrescent, subequally 5-lobed to ca. 1 mm above base; lobes almost colorless, linear, glabrous or sparsely gland-tipped pilose, apex obtuse. Corolla violet, 3.2-4 cm, outside pubescent but silky gray in bud, inside glabrous; tube strongly inflated from near base then widened to ca. 1.5 cm at middle and finally bent to ca. 90° but not narrowed at mouth; lobes ovate, ca. 5 × 7 mm, apex rounded to slightly emarginate. Stamens 4, included; filaments ca. 2.5 mm, all equal in length, glabrous; anther thecae oblong, ca. 1.5 mm. Ovary glabrous; style ca. 2 cm, glabrous or with a few trichomes. Capsule oblong, 1.1-1.2 cm, glabrous, 4-seeded, apex apiculate. Seeds oblong in outline, ca. 3 × 2 mm, covered with stiff white trichomes. Fl. Aug-Sep, fr. Oct-Nov.

Tsuga forests; 2300-2700 m. Xizang (Zayü) [India].