老山蛇根草 lao shan she gen cao

Herbs, suberect, to 50 cm tall; stems sulcate to subterete, drying grayish yellow, subglabrous. Leaves in markedly unequal pairs; petiole 0.3-1 cm, subglabrous; blade drying thinly papery, adaxially gray to blackened, abaxially grayish yellow, ovate, larger ones 6-8(-11) × 2-3 cm, smaller ones 1.5-5 × 1-2 cm, glabrous on both surfaces, base obtuse to acute then decurrent, apex shortly acuminate; secondary veins 6-9 pairs; stipules caducous, not seen. Inflorescence ferruginous mealy puberulent; peduncle 1-2 cm; axes short, helicoid; bracteoles filiform-subulate, ca. 3 mm. Flowers reportedly distylous, subsessile. Calyx mealy puberulent; hypanthium obconic-turbinate, ca. 1 mm, 5-ribbed; lobes triangular to deltoid, ca. 0.4 mm. Corolla white, tubular-funnelform, outside glabrous; tube 9-10 mm, inside near middle with villous fascicles mixed with scalelike pilose trichomes; lobes subovate, ca. 0.7 mm, dorsally with a broad semiorbicular wing. Capsules not seen. Fl. Nov-Jun of following year.

● Wet places in forests. Guangxi.

The protologue reported this species as distylous but described only one floral form, similar to the short-styled flowers of distylous species with the anthers positioned in or shortly above the corolla throat and the stigmas situated near the middle of the corolla tube.