var. lyroglossa

Kurzweil, Hubert, 2010, A precursory study of the Calanthe group (Orchidaceae) in Thailand, Adansonia (3) 32 (1), pp. 57-107 : 75-76

var. lyroglossa

Calanthe foerstermannii Rchb. f., Gardeners’ Chronicle, n.s., 1883: 814 (1883); Hooker, Flora of British India 5: 854 (1890); Seidenfaden & Smitinand, The Orchids of Thailand – A Preliminary List, part III: 335 (1961); Seidenfaden & Smitinand, The Orchids of Thailand – A Preliminary List, part IV, 2: 793 (1965). — Alismorkis foerstermannii (Rchb.f.) Kuntze, Revisio Generum Plantarum 2: 650 (1891). — Type: Eastern Myanmar, Förstermann s.n. (?holo-, W).

Calanthe nephroidea Gagnep. , Bulletin du Muséum national d’Histoire naturelle, sér. 2, 22: 625 (1950). — Type: Vietnam, Pnom Sapoum , Ht. Donnai, in forest, 1000- 1200 m, 23.II.1933, Poilane 22125 (holo-, P!).

ADDITIONAL MATERIAL EXAMINED. — North-Eastern, Loei, Phu Krading, 7-9.XI.1970, Charoenphol et al. 4722 ( AAU); 18.VII.1953, Dee 659 ( BKF); Larsen et al. 4722 (C spirit); 2-3.XI.1984, Murata et al.T 42893 (C spirit, L); XII.1958, Seidenfaden & Smitinand 3145 (C spirit); 3709A (C spirit); 16.XI.1979, Shimizu et al. 23152 ( BKF, C spirit). — North-Eastern, Loei, Phu Luang, 15.XI.1968, Chermisirivatthana 1060 ( BK). — Eastern, Chaiyaphum, Tunkameng, 17.XI.1971, v. Beusekom et al. 4392 ( BKF, C, K, L). — Eastern, Nakhon Ratchasima, Khao Yai, 7.I.1963, Phengklai 706 ( BKF, SING). — Eastern, Nakhon Ratchasima, Khao Lem, 28.XII.1930, Put 3565 (C, K). — Central, Nakhon Nayok, Khao Yai, 5.II.2001, Maxwell 01-37 ( BKF, CMU [Sc], CMU [Sc] spirit). — Peninsular, Ranong, Khao Pawta Leong Kaeo, 29.XI.1973, Santisuk 739 ( BKF, C spirit); 9.XII.1979, Shimizu et al. 26690 ( BKF). — Peninsular, Phangnga, Khao Pawta Leong Kaeo, 27.II.1974, Geesink et al. 7665 ( AAU, B, BKF, C, K, L). — Peninsular, Nakhon Si Thammarat, Khao Luang, 25.I.1966, Hansen & Smitinand 12068 ( BKF, C, SING); Seidenfaden & Smitinand 6277 (C spirit); VIII.[year not given], Smitinand 1300 ( BKF); 17.V.1968, v. Beusekom & Phengklai 828a ( BKF, L). — Peninsular, Pattani, Kao Kalakuri, 10.IX.1923, Kerr 0110 ( BK, C, K, L). — Without locality, BCU Herb. Tr. 1039 ( BCU spirit); Nanakorn et al. 16347 ( QBG spirit) .

ILLUSTRATIONS. — Seidenfaden & Smitinand, The Orchids of Thailand – A Preliminary List, part III: fig.256a-f (1961) [as Calanthe foerstermannii Rchb. f.]; Seidenfaden, Dansk Botanisk Arkiv 29: fig. 8a-f, pl. III on page 27 (1975); Seidenfaden & Wood, The Orchids of Peninsular Malaysia and Singapore: fig. 74g-k, pl. 10b (1992).

DESCRIPTION

Terrestrial herbs, evergreen, glabrous, 43-58 cm tall. Basal sheaths 1-2, linear, to 11(-18.5) × 1 cm, often largely decayed at the flowering time and consisting only of dry veins; once observed with a narrowly lanceolate blade c. 11.5 × 1 cm. Pseudobulbs inconspicuous and largely enclosed by the leaf sheaths, 2-3 cm long, close together, several-noded. Leaves 3-6(-7), perennial, lanceolate-oblong, acuminate, 35-89(-101) × (3.6-) 6-8 cm; with grooved petioles 9-28(-40) cm long. Inflorescences erect, arising from the base of the leafy shoot; peduncles 24-46 cm long; sterile bracts 2-4(-6), scattered along the flowering stem and a few clustered at its base, erect, lanceolate-oblong, acute or subacute, sometimes mucronate, 3-7.5 cm long, sheathing; raceme semi-dense or dense, many-flowered; rachis (5-) 8-19 cm long; floral bracts caducous, ovatelanceolate, acute to acuminate, 21-35 × 3.5-8 mm. Flowers to 10 mm across, yellow, rarely whitish yellow, lip and spur once reported as soon turning black (?drying out), gynostemium pale yellow; flowers reported as odourless. Ovary (6-) 8-14 mm long, with a very pronounced distinction from the 3.5-6 mm long pedicel. Sepals elliptic-lanceolate, acute or acuminate, sometimes shortly caudate, 3- or 5-veined; median sepal 6-9(-10) × 2-5 mm; lateral sepals 7.8-9(-10) × 2.7-7 mm. Petals ovateelliptic, acute or acuminate, 3-veined, 6.5-9(-9.5) × 2.8-5.5 mm. Lip weakly 3-lobed, 7-10 mm long and to 8.3 mm wide, base completely united with the gynostemium, spurred; midlobe reniform or transversally oblong, apex emarginate, 3-4.5(-5) × 5.5-7(-8.3) mm; side lobes small, auriculate, mostly under 0.5 mm long; lip with two small keels near the base; spur cylindric and apically clavate, more or less parallel to the pedicel, 4-6(-7) mm long, sometimes apically slightly bifid. Gynostemium 3-5 mm long, stout; rostellum beaked, stigma cavity rather wide. Fruits ellipsoid, c. 10 × 5 mm.

DISTRIBUTION AND PHENOLOGY

In Thailand found in the North-Eastern, Eastern, Central and Peninsular regions. Elsewhere widespread from India to W Malesia and S China. Found in evergreen forest, also in secondary vegetation, from 725 to 1300 m. Sandstone has been reported as bedrock. Flowering: July-September and November-February.

REMARKS

This species is easily distinguished from all other Thai species of Calanthe sect. Styloglossum because of its small yellow flowers and the minute auriculate lip side lobes.

Only the typical variety is known in our region, var. longibracteata P.O’Byrne occurring in Java. It differs from the typical variety by its very long and persistent floral bracts.