13. Dendrobium heterocarpum Wallich ex Lindley, Gen. Sp. Orchid. Pl. 78. 1830.
尖刀唇石斛 jian dao chun shi hu
Callista aurea (Lindley) Kuntze; C. heterocarpa (Wallich ex Lindley) Kuntze; Dendrobium atractodes Ridley; D. aureum Lindley; D. minahassae Kraenzlin.
Stems often ascending, ± clavate, 5-27 cm, 1-1.5 cm in diam., thickly fleshy, base contracted, thickened toward apex, unbranched, with several ± swollen nodes, internodes 2-3 cm, golden yellow when fresh, sulfur-yellow tinged with dirty black when dry. Leaves oblong-lanceolate, usually 7-10 × 1.2-2 cm, leathery, base with clasping sheath, apex acute or slightly obtuse; leaf sheath papery. Inflorescence a raceme arising from apical part of deciduous old stem, 1-4-flowered; peduncle 2-3 mm; basal sheaths 2 or 3, membranous; floral bracts pale white, broadly ovate, 4-9 mm, membranous, apex obtuse. Pedicel and ovary ca. 2 cm. Flowers scented, spreading; sepals and petals silver-white or creamy yellow, lateral lobes of lip yellow with red striation, mid-lobe silver or creamy yellow, column white, purplish red on sides, yellow on inner surface, foot yellow. Dorsal sepal oblong, 27-30 × ca. 8 mm, 5-veined, apex obtuse; lateral sepals obliquely ovate-lanceolate, ca. as large as dorsal sepal, main veins 7, secondary veins many, base slightly oblique, apex subacute; mentum conic, ca. 7 mm. Petals ovate-oblong, 25-28 × 9-10(or more) mm, main veins 5, secondary veins many, margin entire, apex acute; lip ovate-lanceolate, nearly as long as sepals, inconspicuously 3-lobed; lateral lobes erect, middle part downcurved, adaxially with dense, short, reddish brown hairs, margin entire; mid-lobe acute. Column ca. 3 mm, front (adaxial surface) base slightly dilated; anther cap conic, ca. 2.5 mm, densely finely papillate, front margin denticulate.
Epiphytic on tree trunks in open forests; 1500-1800 m. S and W Yunnan [Bhutan, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Philippines, Sri Lanka, Thailand, Vietnam].