四腺翻唇兰 si xian fan chun lan

Hetaeria biloba (Ridley) Seidenfaden & J. J. Wood; H. grandiflora Ridley; H. hainanensis Tang & F. T. Wang; H. rotundiloba J. J. Smith; Heterozeuxine rotundiloba (J. J. Smith) C. S. Leou; Zeuxine biloba Ridley.

Plants 28-34 cm tall. Stem 3-7-leaved. Leaves scattered along stem, ovate-lanceolate, 3.5-7 × 1.1-2 cm, 3-veined, base obtuse, apex acute or acuminate; petiole-like base and sheath 1.5-2 cm. Inflorescence erect, villous, with 1-3 sterile bracts; rachis laxly to subdensely 4-20-flowered, 2-10 cm; floral bracts lanceolate, ca. 7 mm, abaxially villous, margin ciliate. Flowers white; ovary not twisted, often arcuate, subcylindric or ellipsoid, 7-8 mm including pedicel, hispid. Sepals ca. 5 mm, abaxially sparsely hispid, 3-veined; dorsal sepal elliptic, concave, ca. 2 mm wide, apex acute; lateral sepals ovate, somewhat oblique, ca. 2.4 mm wide, apex acute. Petals linear, ca. 5 × 0.6 mm, glabrous, 1-veined, apex obtuse; lip ca. 5 mm, 3-partite; hypochile concave to shallowly saccate, 5-veined, lateral veins each with 1 lamellate, transversely oblong, hooked callus; mesochile short, ca. 1 mm, margin involute; epichile dilated, ca. 6 mm wide, 2-lobed; lobes strongly revolute but divaricate in unfolded state, suborbicular, ca. 2.5 × 2.5 mm, apex slightly emarginate. Column ca. 3 mm; wings reduced; rostellum arms ca. 1.5 mm. Fl. Feb-Mar.

Dense or sparse forests; 800-1000 m. Hainan, C and S Taiwan [NE India, Indonesia, Laos, Malaysia, Myanmar, Philippines, Thailand, Vietnam].