Volume 12 > Part 3 > Year 2022 > Page 742 > Orchidaceae > Crepidium

20. Crepidium orbiculare (W.W.Sm. & Jeffrey) Seidenf.wfo-0000926978

Contr. Orchid Fl. Thailand XIII: 18. 1997; Sittisudjathum, Wild Orchids Thailand [in Thai]: 175 (incl. colour photos). 2006; Nanakorn & Watthana, Queen Sirikit Bot. Gard. (Thai Native Orchids 1): 195 (incl. colour photos). 2008; S.C.Chen & J.J.Wood in Z.Y.Wu et al. (eds.), Fl. China 25: 231. 2009.— Microstylis orbicularis W.W.Sm. & Jeffrey, Notes Roy. Bot. Gard. Edinburgh 9: 111. 1916.— Malaxis orbicularis (W.W.Sm. & Jeffrey) Tang & F.T.Wang, Acta Phytotax. Sin. 1: 73. 1951; Seidenf. & Smitinand, Orchids Thailand: 150, fig. 118, t. V(2706). 1959; Seidenf., Dansk Bot. Ark. 33(1): 85, fig. 59. 1978; Opera Bot. 114: 150. 1992; Aver., Turczaninowia 16: 129, fig. 63f. 2013. Fig. 397.

Accepted Name : This is currently accepted.

Synonyms & Citations :

Description : Terrestrial plant with a condensed rhizome bearing an erect, pseudobulbous, 18–45 cm tall flowering shoot distally. Pseudobulb ovoid to fusiform, 1–5 cm long, 0.6–1.3 cm in diameter. Foliage leaves 3–4, ascending to spreading or erect, petiolate; petiole 1.2–4.5 cm long; lamina green, unspotted, broadly ovate to lanceolate or (oblong-)elliptic, attenuate to acuminate, 2.2–18 by 1.2–5.5 cm, glabrous, margins undulate. Inflorescence 16–38 cm long, laxly 10- to 45-flowered; peduncle 8–20 cm long; bracts strongly recurved, lanceolate, acuminate, 3–12 mm long. Flowers greenish purple, red-purple to dark purple or maroon, 4–10 mm in diameter. Sepals obtuse to rounded or truncate with revolute margins; dorsal sepal oblong, 5–7.5 by 1–2.5 mm, about twice as long as labellum auricles; lateral sepals oblong to obovate or elliptic, 3–5 by 2–3.5 mm. Petals spreading to reflexed, linear, obtuse, 5–7.5 by 0.5–1 mm. Labellum (nearly) flat, 6.5–9 by 5–10 mm, about as long as wide, suborbicular (not constricted at the middle) with a strongly sagittate-auriculate base, distally rounded with 20–40 variously sized teeth/laciniae; cavity elliptic to suborbicular in outline, bordered by a more or less horseshoe-shaped ridge; auricles broadly and obliquely (ovate-)triangular to lanceolate, obtuse to acute, 2.5–4 by 2–3.5 mm. Column 1.5–2 mm long, larger than the largest marginal labellum teeth; staminodes oblong. Ovary 5–10 mm long.

Thailand : NORTHERN: Chiang Mai, Tak (Umphang).

Distribution : Myanmar, Yunnan (type), Vietnam.

Ecology : Crepidium orbiculare grows in shaded areas and open grasslands in primary hill evergreen forests on granite bedrock, 1,000–1,800 m alt. Flowering: June–September.