峨嵋茜草 e mei qian cao

Vines, herbaceous, to 3 m; stems quadrangular or narrowly 4-winged, sparsely retrorsely aculeolate on angles. Leaves opposite; petiole 1-4(-6) cm, retrorsely aculeolate and sometimes ferruginous hirtellous; blade drying thickly papery to leathery, light green and ± ferruginous, particularly below and on main veins, ovate, lanceolate, or oblanceolate, larger leaves 4-12.5 × 1.5-5(-7) cm, smaller 2-3 × 1-2 cm, glabrous to hirtellous, retrorsely aculeolate at least along veins on both surfaces, base rounded to cordate, margins serrulate-aculeolate, apex acuminate; principal veins 3 or mostly 5; stipules conspicuous, persistent, ± broadly ovate, (5-)10-60 × (4-)8-40 mm, acuminate. Inflorescences predominantly axillary, with several- to many-flowered cymes; axes glabrous to hirtellous, sparsely aculeolate; bracts ovate or sublanceolate, 1-5 mm; pedicels 1-4 mm. Ovary ca. 1 mm, glabrous to glabrescent. Corolla yellow to green, 5-merous, cup-shaped to campanulate, 3.5-4.5 mm in diam., papillose to ± hairy outside; tube 0.8-1.3 mm; lobes triangular-ovate, 1.5-1.7 mm, caudate. Mericarp berry black, 4-5 mm in diam. Fl. Jun-Jul, fr. Aug-Oct.

● Broad-leaved subtropical forests; 1200-1500 m. Sichuan, Yunnan.

The above description of Rubia magna combines data from the protologue, H. S. Lo in FRPS (71(2): 295, t. 63, f. 1-8. 1999), and new collections from the Gaoligong Shan region of Yunnan. The latter are conspicuous by their lack of hairiness and their conspicuous stipules (much larger than shown in FRPS). Certain discrepancies (protologue: leaves sometimes sessile and opposite but sometimes petiolate and 3-5-verticillate; H. S. Lo (loc. cit.: 294): corolla lobes 4) may be due to mixed material and still need clarification.

Rubia magna is mainly characterized by its opposite leaves, dried green and ferruginous blades, and large stipules. It belongs, together with R. falciformis and R. filiformis, to the closely related R. siamensis group from SW China and adjacent areas.

Originally, Rubia magna was described as "a new species of medicinal Rubia," and presumably its uses are detailed in that article.