5. Ophiorrhiza brevidentata H. S. Lo, Bull. Bot. Res., Harbin. 10(2): 32. 1990.
短齿蛇根草 duan chi she gen cao
Herbs, ascending; stems drying purplish red or purplish brown, slender, terete, densely hirtellous. Leaves in markedly unequal pairs; petiole ca. 1 cm, pilosulous; blade drying papery, ovate, larger ones 2-6 cm, smaller ones 1/3-1/2 as large, strigose adaxially, villous abaxially at least along principal veins, base rounded to obtuse, apex cuspidate; secondary veins 9-11(-15) pairs; stipules lanceolate, 5-6 mm, villous, acuminate. Inflorescences congested-cymose to subcapitate, few to many flowered, densely pilosulous; peduncle 1.5-4.5 cm; axes helicoid; bracts oblong-lanceolate or elliptic-oblong, 5-7 mm, ciliate. Flowers with biology unknown. Calyx pilosulous; hypanthium ca. 1.2 mm; lobes subtriangular, 0.7-0.9 mm. Corolla pink or purplish red, tubular, outside glabrous or in bud puberulent at apex; tube ca. 11 mm, inside villous above middle and in throat; lobes ca. 1.5 mm, dorsally with very short horn. Capsule ca. 2 × 6 mm, puberulent. Fl. Apr-May, fr. Jun.
● Streamsides in forests. Yunnan.
The flowers described in the protologue resemble the short-styled form of distylous species, with the anthers shortly exserted in the throat and the stigmas positioned near the base of the corolla tube.