齿瓣石豆兰 chi ban shi dou lan

Bulbophyllum insulsum (Gagnepain) Seidenfaden; Cirrhopetalum insulsum Gagnepain.

Rhizome creeping, slender. Pseudobulbs close, subcylindric or bottle-shaped, 5-10 mm, 2-4 mm in diam., with a terminal leaf. Petiole 4-10 mm; leaf blade narrowly oblong or obovate-lanceolate, 3-4(-9) × 0.5-0.7(-1.4) cm, thinly leathery, base contracted into petiole, margin slightly undulate, apex subacute. Scape from base of pseudobulb, erect, 3-5 cm, longer than leaves, slender, glabrous; raceme shortened, umbel-like, often 2-6-flowered; peduncle ca. 0.5 mm in diam., sparsely with 2 or 3 tubular sheaths; floral bracts erect, narrowly lanceolate, 2-3.5 mm, apex acuminate. Pedicel and ovary longer than floral bracts. Flowers thinly textured, white tinged with purple. Dorsal sepal ovate-lanceolate, concave, 4-5 × 1.5-2 mm, abruptly contracted and thickened above middle, margin denticulate, apex acute; lateral sepals obliquely ovate-lanceolate, 5-5.5 × 1.5-2 mm, thickened above middle, base adnate to column foot forming a mentum, margins entire, apex cuspidate. Petals connivent to sepals, ovate-lanceolate, ca. 3.5 × 1.5 mm, margins denticulate, apex long acuminate; lip recurved, lanceolate in outline, 2-2.5 mm, nearly fleshy, basal half grooved, base attached to end of column foot, immobile, margin entire, apex subacute. Column ca. 1.2 mm; stelidia filiform, ca. 0.5 mm; foot curved, ca. 1.5 mm, with free part ca. 0.5 mm; anther cap subglobose, apex narrowed and beaked, with a densely finely papillate ridge centrally. Fl. May-Aug.

Tree trunks in forests, rocks along valleys; ca. 800 m. Fujian, S Guangdong, Guangxi, SE Hunan, SW Jiangxi, W to SE Yunnan, Zhejiang [Vietnam].