39. Ophiorrhiza macrantha H. S. Lo, Bull. Bot. Res., Harbin. 10(2): 28. 1990.
大花蛇根草 da hua she gen cao
Herbs, weak at base, ascending to erect above, to 50 cm tall; stems drying orange, subglabrous or puberulent when young. Leaves in unequal pairs; petiole 1-4 cm, glabrous or puberulent; blade drying thinly papery or papery, adaxially grayish green, pale or yellowish green abaxially, oblong-ovate, subovate, or elliptic-oblong, 4-16 × 1.8-4.5 cm, glabrous on both surfaces or abaxially puberulent along principal veins, base obtuse to subrounded, margins usually undulate, apex caudate; secondary veins 7-9 pairs; stipules generally persistent, narrowly triangular, 6-8 mm, with globose gland at apex and at each side of base. Inflorescences cymose, many flowered, puberulent; peduncle 2-2.5 cm; axes helicoid, 0.5-2 cm; bracteoles linear-spatulate, ca. 2 mm, ciliolate. Flowers distylous, on pedicels 1.5-3 mm. Calyx puberulent to glabrescent; hypanthium rhomboid-subglobose, ca. 2.5 × 2 mm, 10-ribbed; lobes triangular, subequal or unequal, 1.5-2 mm. Corolla reddish or pink, funnelform, glabrous outside, inside with sparsely white villous ring at middle of tube and sparsely villous above this and sometimes onto lobes; tube 22-23 mm; lobes subovate, ca. 5.5 mm, dorsally with wing ca. 0.8 mm wide with very short apical spur, apex rostrate. Immature capsules submitriform, ca. 3 × 7-7.5 mm, 10-ribbed. Fl. Mar.
● Streamsides in dense forests; ca. 3000 m. Yunnan.
In the protologue and FRPS (71(1): 129-131. 1999), H. S. Lo noted that the long-styled flowers have the anthers positioned near the middle of the corolla tube and the stigmas in its throat, while the short-styled flowers have the anthers positioned in the throat and the stigmas below them inside the upper part of the corolla tube.