6. Ophiorrhiza cana H. S. Lo, Bull. Bot. Res., Harbin. 10(2): 20. 1990.
灰叶蛇根草 hui ye she gen cao
Herbs, creeping; stems drying compressed, striate or shallowly sulcate, pilosulous. Leaves in subequal pairs; petiole 1-1.5 cm, pilosulous; blade drying thinly papery or membranous-papery, leaden gray or sometimes green adaxially, pale and puncticulate abaxially, ovate, elliptic-oblong, or lanceolate, 3.5-11 × 1.8-4.5 cm, adaxially subglabrous or sparsely puberulent, abaxially pilosulous along principal veins, base cuneate to rarely subrounded, margins flat or undulate, apex acute or obtuse then acuminate; secondary veins 10-15 pairs; stipules persistent, broadly triangular then abruptly contracted, 4-5 mm, caudate-acuminate. Inflorescences congested-cymose, many flowered, densely pilosulous, branched to 1 order; peduncle shorter than 1 cm; axes very short, helicoid; bracteoles quickly caducous, ca. 0.3 mm. Flowers distylous, subsessile or with pedicels to 1 mm. Calyx with hypanthium subglobose to subturbinate, ca. 1.1 × 1.5 mm, 5-ribbed, hispidulous; lobes linear, 1.4-1.6 mm, with line of stiff hairs. Corolla drying orange-yellow, tubular-funnelform, hirtellous outside; tube ca. 5 mm, with villous ring in throat; lobes subovate, ca. 2 mm, acute, dorsally with horn ca. 1.5 mm. Capsules obcordate, ca. 2 × 5 mm, hispidulous.
● SE Yunnan.
The protologue described both the long-styled and short-styled forms in detail, noting that the forms have similar calyces and corollas but differ in their stamen and stigma position (i.e., stamens inserted in the corolla tube ca. 0.5 mm from the base and stigmas positioned in the throat in the long-styled form vs. stamens inserted in the throat and stigmas positioned just below the throat in the short-styled flowers). The protologue also noted that this species is known only from the type, which lacks locality or date.