Volume 12 > Part 1 > Year 2011 > Page 26 > Orchidaceae > Brachycorythis

4. Brachycorythis laotica (Gagnep.) Summerh.

Kew Bull. 1955: 236. 1955; Seidenf., Opera Bot. 114; 41, fig. 17. 1992; H.A.Pedersen, Bot. J. Linn. Soc. 162: 72. 2010.— Habenaria laotica Gagnep., Bull. Soc. Bot. France 78: 71. 1931.— Phyllomphax laotica (Gagnep.) Szlach., Richardiana 6: 77. 2006. Fig. 11.

Accepted Name : This is currently accepted.

Description : Flowering shoots 12–18 cm tall, measuring 3.8–6(–6.4) cm from node of the lowermost to node of the uppermost foliage leaf; internodes 0.8–1.4(–1.5) cm long on average. Foliage leaves 4–6(–9); longest leaf (linear-)lanceolate, acute, 6.4–7.9(–9.2) by 1.3–1.5 cm: uppermost leaf (5.1–)5.8–7.2(–8.2) cm long. Inflorescence 2- to 5-flowered; lowermost bract 5.1–6.4 cm long; flowers white to purple or pale green, labellum often with purple lines and/or with a bright yellow blotch at base. Sepals obtuse to rounded; dorsal sepal lanceolate, 12–15.3(–17.6) by 4.8–6.5 mm; lateral sepals falcately lanceolate. Petals free from column, broadly and obliquely lanceolate, subacute, 11–15 by 4.3–5.7 mm. Labellum subcircular to broadly ovate, acute to obtuse, (13.3–)16.6–21 by (12.8–)14.5–18 mm; spur cylindric, 10–13 mm long, 2.6–3.6 times as long as vertical diameter of entrance. Column (1.9–)2.2–3.4 mm long to apex of auricles. Capsule not seen.

Thailand : NORTHERN: Phayao, Lampang (Chae Son), Tak (Mae Ping), Phitsanulok (Thung Salaeng Luang); NORTH-EASTERN: Phetchabun (Nam Nao).

Distribution : Cambodia (type), Vietnam.

Ecology : Mixed deciduous forests, seasonal evergreen forests and bamboo thickets; 400–700 m alt. Flowering: May–September.

Notes: The oldest known Thai collection of Brachycorythis laotica dates back to 1954 (Bunnak 130 -BKF!), but it was not until recently that the occurrence of this species in Thailand was recognized (Pedersen 2010).