Cephalantheropsis obcordata (Lindl.) Ormerod

Kurzweil, Hubert, 2010, A precursory study of the Calanthe group (Orchidaceae) in Thailand, Adansonia (3) 32 (1), pp. 57-107 : 102-104

Cephalantheropsis obcordata (Lindl.) Ormerod

( Fig. 11 )

Orchid Digest 62: 157 (1998); Chen et al., Flora of China,

vol. 25: 289 (2009). — Bletia obcordata Lindl. , Genera

and Species of Orchidaceous Plants: 123 (1831). — Type:

North-eastern India, Sylhet, Wallich s.n. (not found).

Calanthe gracilis Lindl. , Genera and Species of Orchidaceous Plants: 251 (1833); Hooker, Flora of British India 5: 855 (1890). — Limatodis gracilis (Lindl.) Lindl. , Folia Orchidacea 6: 11 (1855). — Alismorkis gracilis (Lindl.) Kuntze, Revisio Generum Plantarum 2: 650 (1891). — Paracalanthe gracilis (Lindl.) Kudô , Journal of the Society of Tropical Agriculture 2: 236 (1930). — Cephalantheropsis gracilis (Lindl.) S.Y.Hu, Quarterly Journal of the Taiwan Museum 25: 213 (1972); Seidenfaden, Nordic Journal of Botany 2: 216 (1982); Seidenfaden, Opera Botanica 89: 38 (1986); Seidenfaden, Opera Botanica 114: 102 (1992); Seidenfaden & Wood, The Orchids of Peninsular Malaysia and Singapore: 180 (1992). — Gastrorchis gracilis (Lindl.) Aver., Preliminary List of Vietnamese Orchids: 203 (1988). — Type:North-eastern India, Sylhet, Wallich s.n., Wallich’s Catalogue 7341 (holo-, K-LINDL!; iso-, K-WALL!).

Calanthe tubifera Hook. f., Flora of British India 5: 855 (1890). — Alismorkis tubifera (Hook.f.) Kuntze, Revisio Generum Plantarum 2: 650 (1891). — Type: Upper Myanmar, Ava, Griffith 5279 (holo-, K!).

Calanthe bursicola Gagnep. , Bulletin du Muséum national d’Histoire naturelle, sér. 2, 22: 509 (1950). — Type: Vietnam, Upper Donnai , Sapoum, 23.II.1933, Poilane 22124 (holo-, P!).

Phaius longipes auct. non (Hook.f.) Holttum: Seidenfaden & Smitinand, The Orchids of Thailand – A Preliminary List, part III: 329 (1961); Seidenfaden & Smitinand, The Orchids of Thailand – A Preliminary List, part IV, 2: 792 (1965).

ADDITIONAL MATERIAL EXAMINED. — North-Eastern,

Loei, Phu Krading , 7-9.XI.1970, Charoenphol et al. 4710

(BKF, K, P, SING); X.1951, Dee 461 ( BKF) ; 7.IX.1911,

Larsen et al. 470 (C spirit); 1.XI.1984, Murata et al. T

42512 (L); 1.XI.1984, T 42689 ( BKF, L) ; 16.XI.1979,

Shimizu et al. 23147 (BKF, C spirit); XII.1958, Sø-

rensen et al. 6197 (BKF, C); 28.XI.1965, Tagawa et

al. T 549 (BKF, C spirit); 16.XII.19634, Umpai 148

(BK); 24.XII.1971, v. Beusekom et al. 4560 ( BKF, C,

C spirit, K, L, P). — North-Eastern, Loei, Phu Luang,

15.XI.1968, Chermisirivatthana 1107 ( BK) ; 5.XII.1965, Tagawa et al. T 1563 ( BKF, C spirit). — South-Western, Kanchanaburi, Khao Ri Yai , 1.II.1926, Kerr 0269 (B, BK, C, C spirit, K, L, P). — Central, Nakhon Nayok, Khao Yai , 8.III.1964, Hansen et al. 11383 ( BKF, C, K); Kitichate 180 ( BCU spirit) ; 17.II.1983, Niyomdham 532 ( BKF) ; 8.III.1964, Seidenfaden & Smitinand 5832 (C spirit). — Central , Nakhon Nayok , 18.II.1983, Menzies & DuPuy 35 (K spirit). — South-Eastern, Prachin Buri, Khao Yai , 16.II.1966, Hennipman 3945a (L). — South-Eastern, Prachin Buri, Thaithong 983 ( BCU spirit). — Peninsular, Ranong, Khao Pawta Luang , 1.II.1929, Kerr 0702 ( BK, C, C spirit, K). — Peninsular , Trang, Khao Sung, Kerr 0573 (K). — Unspecified, Khao Yai, Cumberlege 739 ( BKF spirit) ; III. 1964, 1071 ( BKF spirit, K spirit). — Without locality, Chueachan s.n. ( QBG spirit 17587) .

ILLUSTRATIONS. — Seidenfaden & Smitinand, The Orchids of Thailand – A Preliminary List, part III: fig. 251a-c (1961) [as Phaius longipes (Hook.f.) Holttum]; Seidenfaden, Opera Botanica 89: fig. 17a-i, pl. IIIb (1986) [as Cephalantheropsis gracilis (Lindl.) S.Y.Hu ]; Seidenfaden & Wood, The Orchids of Peninsular Malaysia and Singapore: fig.77a-i (1992) [as C. gracilis (Lindl.) S.Y.Hu ]; Ormerod, Orchid Digest 62: figs. 1d, e, 2g-i (1998).

DESCRIPTION

Terrestrial or epilithic herbs, evergreen, 50-90 cm tall; stems cane-like, narrowly fusiform-cylindric, 37-55 × 0.5-1 cm, several-noded. Basal sheaths erect, tubular, 4-10.1 cm long, the upper sometimes with a foliose blade up to 5 × 2 cm, thereby grading into the leaves. Leaves 3-9, arising from the stem all along its length or only in the upper half, ellipticlanceolate, acuminate, (17-)22-37(-62) × (2.8-) 3- 5.7 cm, glabrous; with petioles 3-11(-20) cm long; sheathing leaf bases forming a pseudostem 2-5 cm long. Inflorescences 1-2, 30- 66 cm long, arising in an axillary position on the sides of the leafy shoot in its lower half, hirsute (sometimes very sparsely so at the base); peduncles (15-) 25-45 cm long; sterile bracts (3-)4-8, scattered along the flowering stem and a few clustered at its base, erect, elliptic-lanceolate, acute, sheathing, (0.6-) 2.1-4.6 cm long, subglabrous or sparsely hairy; sometimes already fallen off at the flowering time and only the leaf scars visible; raceme lax or semi-dense, 15- to many-flowered; rachis (5-) 10-20 cm long, with hirsute hairs that sometimes have a pink tinge; floral bracts caducous, narrowly lanceolate, long-acuminate, glabrous. Flowers 20-30 mm across, yellow or orange-yellow, also recorded as sepals and petals brownish-yellow and lip white with brown patch on the disk. Ovary indistinguishable from the pedicel, (15-) 18-26 mm long, densely hairy. Sepals similar, linear to oblongelliptic, acute, 3-veined, 10-19 × 2-6.8 mm, hairy on the outside especially in their upper part, inside glabrous or with scattered hairs. Petals obovatelanceolate, acute, 3-veined, 10-18 × 2-4.5 mm, hairy or subglabrous. Lip 3-lobed, 8-15(-18) × 5-10(-14) mm, united with the gynostemium only at the very base, spurless, base pubescent, two lateral areas with short and rather stout hairs near the upper end of the side lobes, otherwise glabrous; midlobe flabellate, bilobulate, 3.5-8 × 5-10 mm, decurved, margin crispate; side lobes erect, falcate, tips pointing forwards, 1.7-5 × 1-3 mm; disk with two longitudinal ridges over most of its length or only in its basal half. Gynostemium 3-6 mm long, densely hairy. Fruits not seen.

DISTRIBUTION AND PHENOLOGY

In Thailand found in all regions except the North and East. Generally widespread from NE India to S China and Japan, and in Malesia as far eastwards as the Moluccas. Found in dry evergreen forest from about 1100 to 1400 m. Once reported over sandstone. Flowering from September to December and from February to March.

REMARKS

Easily recognized by the many-flowered inflorescences which arise in lateral position on the canelike stems and the small or medium-sized spurless yellow flowers.

Cephalantheropsis obcordata was previously widely known as Calanthe gracilis and, after its transfer to the genus Cephalantheropsis , as Cephalantheropsis gracilis . As the species was later shown to be conspecific with Bletia obcordata Lindl. , its name had to change to Cephalantheropsis obcordata , which is the older epithet.

Figures

FIG. 11. — Cephalantheropsis obcordata (Lindl.) Ormerod: A, plant; B, flower; C, median sepal; D, petal; E, lateral sepal; F, lip; G, lip and gynostemium; H, gynostemium;I, pollinia. A, Evrard 2083; B-I, Seidenfaden & Smitinand 5832. Reproduced with permission from the University of Copenhagen, drawn by Poul Juul. Scale bars: A, 10 cm; B-H, 1 cm; I, 1 mm