Calanthe sylvatica (Thouars) Lindl., Gen. Sp. Orchid. Pl.: 250 (1833).
Centrosis sylvatica Thouars, Hist. Orchid.: t. 35 (1822).
Bletia sylvatica (Thouars) Bojer, Hortus Maurit.: 318 (1837).
Alismorkis centrosis (Thouars) Steud., Nomencl. Bot., ed. 2, 1: 49 (1840).
Centrosis corymbosa Thouars, Hist. Orchid.: t. 35 (1822).
Centrosis plantaginea Thouars, Hist. Orchid.: t. 35 (1822).
Centrosia aubertii A.Rich., Mém. Soc. Hist. Nat. Paris 4: 40 (1828).
Calanthe sylvestris Lindl. ex Steud., Nomencl. Bot., ed. 2, 1: 253 (1840), orth. var.
Calanthe sylvatica var. natalensis Rchb.f., Linnaea 19: 374 (1846).
Calanthe natalensis (Rchb.f.) Rchb.f., Bonplandia (Hannover) 4: 322 (1856).
Calanthe corymbosa (Thouars) Lindl., J. Linn. Soc., Bot. 6: 129 (1862).
Calanthe sanderiana B.S.Williams, Nursery Cat. (B.S.Williams) 1887: 21 (1887).
Alismorkis natalensis (Rchb.f.) Kuntze, Revis. Gen. Pl. 2: 650 (1891).
Alismorkis plantaginea (Thouars) Kuntze, Revis. Gen. Pl. 2: 650 (1891).
Calanthe sanderiana Rolfe, Gard. Chron., ser. 3, 12: 396 (1892), nom. illeg.
Calanthe delphinioides Kraenzl., Bot. Jahrb. Syst. 17: 55 (1893).
Calanthe volkensii Rolfe in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 7: 46 (1897).
Calanthe neglecta Schltr., Bot. Jahrb. Syst. 53: 570 (1915).
Calanthe stolzii Schltr., Bot. Jahrb. Syst. 53: 569 (1915).
Calanthe sylvatica var. pallidipetala Schltr., Repert. Spec. Nov. Regni Veg. 33: 166 (1924).
Calanthe schliebenii Mansf., Notizbl. Bot. Gart. Berlin-Dahlem 11: 808 (1933).
Calanthe humbertii H.Perrier, Mém. Inst. Sci. Madagascar, Sér. B, Biol. Vég. 6: 258 (1955).
Calanthe candida Bosser, Bull. Mus. Natl. Hist. Nat., B, Adansonia 11: 34 (1989).
Calanthe sylvatica var. geerinckiana Stévart, Syst. Geogr. Pl. 70: 147 (2000).
Plant size and type: A terrestrial plant with clustered growths to about 14 in. (40 cm) tall. The extreme variability of this species has resulted in the large number of synonyms. Pseudobulb/stem: 0.4-0.8 in. (1-2 cm) long by about 0.4 in. (1 cm) thick. The small pseudobulb is narrowly conical and is enclosed by the longitudinally folded leaf bases. Leaves: 8-16 in. (20-40 cm) long by 7 in. (17 cm) wide. Two to six broadly lanceolate leaves are or elliptic to obovate leaves are carried on each growth. The leaves have about 5 nerves with longitudinal fanlike folds, are sharply pointed at the tip, are slightly undulate, taper below to where they are attached to the narrow, longitudinally folded petiole at the base, which may be up to 4-6 in. (10-15 cm) long. The leaves are deciduous at the end of the growing season, leaving the pseudobulb enclosed by the old leaf bases. Inflorescence: 12-20 in. (30-50 cm) long by about 0.2 in. (0.4 cm) in diameter. The scape arises from the center of the annual growth and is covered with short hairs. Flowers are loosely arranged in a 4 in. (10 cm) long raceme at the apex of the scape, each blossom with a lanceolate floral bract that is about 0.8 in. (2 cm) long. The bracts toward the apex of the raceme are somewhat smaller, however. Each blossom is carried on a pedicel and ovary that are densely hairy and have a combined length of 1.0-1.4 in. (2.6-3.5 cm). Flowers: 15-25 per inflorescence. The flowers, which are up to 2 in. (5 cm) across, are pale purple to white with a yellow callus. The dorsal sepal is somewhat elliptic, sharply pointed, and 0.7-0.9 in. (1.8-2.3 cm) long by 0.2-0.4 in. (0.6-1.0 cm) wide. The oblong lateral sepals are sharply pointed and measure 0.8-1.1 in. (2.0-2.8 cm) long by 0.2-0.3 in. (0.6-0.7 cm) wide. Petals are obovate or broadly oblong. bluntly pointed, and measure 0.5-0.8 in. (1.5-2.0 cm) long by 0.4-0.5 in. (0.9-1.2 cm) wide. The 3-lobed lip is 0.8-0.9 in. (2.0-2.3 cm) long and fused at the base to the margins of the entire column. It may or may not have side lobes. If lateral lobes are present, they are narrow, spreading, and measure 0.2-0.3 in. (0.45-0.8 cm) long by 0.1 in. (0.25-0.3 cm) wide. The midlobe is fan- or kidney-shaped, slightly bilobed at the apex, is 0.4-0.6 in. (1.0-1.5 cm) wide, and is sometimes slightly decurved and folded at the apex . The disc has a cluster of tubercles arranged in 3 rows at the base. The spur at the base of the lip is cylindrical, sparsely hairy on the outside, is curved to S-shaped to incurved, and is 1.0-2.0 in. (2.5-5.0 cm) long. The column is up to 0.2 in. (0.4 cm) long.
In forests, between 300 and 2000 mm. alt.; flowering: January-April; widely represented.
This species is variable as to the size and coloration of the flowers, the dimensions of the various parts of the flowers and the ornamentation at the base of the labellum.
Trop. & S. Africa, W. Indian Ocean
Beaman, T., J. J. Wood, R. S. Beaman, and J. H. Beaman. 2001. Orchids of Sarawak. Natural History Publications (Borneo), Kota Kinabalu in association with Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AE, England. Chen, Singchi, Zhanou Tsi, and Luo Yibo. 1999. Native Orchids of China in Colour. Science Press. Beijing, New York. Comber, J. 1990. The orchids of Java. Royal Botanic Gardens, Kew, Richmond, Surrey, England. Comber, J. 2001. Orchids of Sumatra. The Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, England. Dassanayake, M., and E. Fosberg. 1981. Flora of Ceylon. A revised handbook. vol. 2. Oxford and IBH Publishing Co., New Delhi, India. Hamilton (1988) Lin, Tsan-Piao. 1975. Native orchids of Taiwan. vol. 1. Southern Materials Center, P. O. Box 13-342, Taipei, Taiwan, Republic of China. Pearce, N. and P. Cribb. 2002. The Orchids of Bhutan. The Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh EH3 5LR and the Royal Government of Bhutan. Seidenfaden, G. 1975. Orchid genera in Thailand—1, 2, 3. 1 Calanthe R. Br; 2 Cleisostoma Bl.; 3 Coelogyne Lindl. Dansk Botanisk Arkiv Bind 29—Nr. 2-4. Seidenfaden, G., and J. J. Wood. 1992. The orchids of peninsular Malaysia and Singapore. Published in association with The Royal Botanic Gardens, Kew and Botanic Gardens, Singapore. Olsen and Olsen, Helstedsvej 10, DK-3480 Fredensborg, Denmark. Wood, J. J., and P. Cribb. 1994. A checklist of the orchids of Borneo. Royal Botanic Gardens, Kew.
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