53. Ophiorrhiza pumila Champion ex Bentham, Hooker’s J. Bot. Kew Gard. Misc. 4: 169. 1852.
短小蛇根草 duan xiao she gen cao
Ophiorrhiza aureolina H. S. Lo f. qiongyaensis H. S. Lo; O. humilis Y. C. Tseng; O. inflata Maximowicz; O. pumila var. inflata (Maximowicz) Masamune.
Herbs, weak to ascending, to 20(-30) cm tall; stems drying gray or grayish yellow, weakly rugose, densely tomentulose-villosulous. Leaves in subequal pairs; petiole 0.1-1.5 cm, densely tomentulose; blade drying papery, adaxially green, grayish green, or dark grayish brown, abaxially pale to red, ovate, lanceolate, elliptic, or elliptic-oblong, (0.5-)2-5.5(-9) × (0.4-)1-2.5 cm, adaxially subglabrous to sparsely strigillose or hispidulous, abaxially densely puberulent to tomentulose or sometimes glabrescent, base cuneate and generally decurrent, margins entire to somewhat undulate, apex acute to obtuse, subacuminate, or rounded; secondary veins 5-8 pairs; stipules caducous, linear, 1-3 mm, puberulent. Inflorescences congested-cymose, several to many flowered, densely tomentulose-puberulent; peduncle 0.3-1.2 cm; branched portion 5-10 × 10-12 mm; axes becoming helicoid; bracts few, narrowly triangular to linear, 0.3-2 mm. Flowers homostylous, subsessile or on pedicels to 1.5 mm. Calyx with hypanthium subglobose, 0.8-1.2 mm, 5-ribbed, densely hispidulous except ribs glabrescent; lobes subtriangular to linear, 0.3-0.6 mm, glabrescent. Corolla white, tubular to inflated, outside puberulent to hispidulous; tube 2.5-2.8 mm, with villous ring in throat to villosulous throughout inside; lobes ovate-triangular, 1.2-1.5 mm, dorsally weakly ribbed, acute to obtuse. Capsules drying brownish yellow, mitriform or somewhat obcordate, 2-2.5 × 5-7 mm, hispidulous. Fl. Apr-Sep, fr. Jun-Oct.
Shady places on wet lands, streamsides or riversides in forests; 200-700 m. Fujian, Guangdong, Guangxi, Hainan, Jiangxi, Taiwan, Yunnan [Japan, N Vietnam].
The floral biology of this species was studied by Nakamura et al. (J. Jap. Bot. 81: 113-120. 2006), who found the plants studied in the Ryukyu Islands and Taiwan to be long-styled-monomorphic, not distylous as previously reported. They also observed very low pollination rates in wild plants and concluded that probably at least much of the reproduction in this species is through autogamy.
This species was reviewed recently by Duan and Lin (Acta Phytotax. Sin. 45: 878-879. 2007), who newly synonymized several names under Ophiorrhiza pumila but separated relatively smaller plants in O. humilis. However, these smaller plants were included within the circumscription of O. pumila by H. S. Lo (in FRPS 71(1): 171. 1999), who is followed here.