大山雙葉蘭

Plants 11-17 cm tall. Stems erect, 7-12 cm long below leaves, base with one sheath. Leaves deltoid or ovate-semiorbicular, 2-2.6 cm long, 2.5-2.7 cm wide, acute or mucronate at apex, cuspidate-truncate or triangular-truncate at base, entire, glabrous on both surfaces, with reticulate veins. Raceme 2-4 cm long, 10-15-flowered, peduncle and rachis puberulous, peduncle with few bract-like scales; bracts ovate-lanceolate, 3-4 mm long, 1-1.5 mm wide, acute, 1-nerved; pedicel and ovary 5-6 mm long, pedicel glabrous or slightly puberulous. Flowers spreading; dorsal sepal lanceolate, 2-2.2 mm long, 0.6- 0.7 mm wide, acute, 1-nerved; lateral sepals falcate, 2.5 mm long, 0.8-1 mm wide, acute, 1-nerved; petals linear, 2.3 mm long, 0.4 mm wide, acute, 1-nerved; lip spatulate, 3.5-4.5 mm long, slightly narrowed and 0.5-1 mm wide near base, apex dilated to 1.5-2 mm wide, cordate-emaginate or shallowly 2-lobed, with triangular tooth at sinus; column 1.5-1.8 mm long, erect, slightly dilated at top, with short stalk at base; anther ellipsoid, 0.5 mm long; stigma semiorbicular; rostellum ovate, protruding.

ILAN: Nanhutashan, Masamune et al. 3065; Su 8376.

Endemic. Known only from Nanhutashan at ca. 1,800 m.