4. Tropidia angustifolia C. L. Yeh & C. S. Leou, Taiwania. 54: 140. 2009.
狭叶竹茎兰 xia ye zhu jing lan
Plants 10-20 cm tall. Rhizome ascending; roots rigid, filiform. Stem erect, slender, unbranched. Leaf usually solitary, occasionally 2, linear-lanceolate to narrowly ovate-lanceolate, 8-10.5 × 1.7-2.1 cm, base cuneate, apex acuminate. Inflorescence terminal, 5-6 cm, 9-12-flowered; bracts lanceolate, glabrous. Flowers not resupinate, whitish, tinged pale green at apex of sepals and petals, tinged orange at apex of lip, glabrous; pedicel and ovary 5-7 mm. Dorsal sepal free, oblong, ca. 6.5 × 2.5 mm, apex subacute; lateral sepals almost completely connate and forming a synsepal; synsepal ca. 8 mm, bilobed at apex, slightly concave at base, apex reflexed. Petals slightly concave, oblong, slightly oblique, 6.5-7 × ca. 2.8 mm, keeled abaxially, apex acute; lip oblong-ovate, ca. 5 × 3 mm, concave-saccate at base, apex recurved; disk with 2 longitudinal ridges toward base. Column ca. 3 mm including rostellum; anther ovate, ca. 1.8 mm, apex rounded; pollinia clavate, ca. 1.7 mm, stipe linear; viscidium ovoid; stigma transversely elliptic. Fl. Jul-Aug.
● Broad-leaved evergreen forests; 600-800 m. S Taiwan.