Thelasis khasiana J. D. Hooker Fl. Brit. India. 6: 87. 1890.

滇南矮柱兰 dian nan ai zhu lan

Thelasis pygmaea (Griffith) Blume var. khasiana (J. D. Hooker) Schlechter.

Pseudobulbs contiguous, ovoid, 1-1.5 × 1-1.5 cm, apex with 1 leaf or sometimes with another smaller leaf. Larger leaf blade oblanceolate-linear or narrowly oblong, 9-12 × 1.2-1.5 cm, base contracted into petiole 1.5-2 cm, apex obtuse; smaller leaf blade (if present) subelliptic, ca. 1 cm. Inflorescence arising from base of pseudobulb, 16-19 cm, scape slender, with 2 or 3 tubular sheaths below middle; rachis slightly arching, 6-7 cm, 20- or more flowered; floral bracts ovate-lanceolate, 2-2.5 mm. Flowers yellowish green, not opening widely; pedicel and ovary 2-2.5 mm. Dorsal sepal ovate, 2.5-3.1 × ca. 1.5 mm, acuminate; lateral sepals similar to dorsal sepal, slightly cymbiform, abaxially not keeled or sometimes base slightly ridged. Petals narrowly oblong, 2.1-2.4 × ca. 0.8 mm; lip ovate-lanceolate, ca. 3 × 1.3 mm, margin not involute. Column short. Fl. Jul.

Epiphytic on tree trunks in open forests; 900-2000 m. S Yunnan [India, Thailand, N Vietnam].