Calanthe humblotii (Rchb.f.) M.W.Chase, Christenh. & Schuit., Phytotaxa 472: 163 (2020).
Homotypic Names:
Phaius humblotii Rchb.f., Gard. Chron., n.s., 14: 812 (1880).
Gastrorchis humblotii (Rchb.f.) Schltr., Repert. Spec. Nov. Regni Veg. Beih. 33: 169 (1924).
Heterotypic Synonyms:
Gastrorchis schlechteri H.Perrier, Bull. Trimestriel Acad. Malgache, n.s., 12: 33 (1930).
Phaius schlechteri (H.Perrier) Summerh., Kew Bull. 17: 560 (1964).
Phaius humblotii var. ruber Bosser, Adansonia, n.s., 11: 526 (1971).
Phaius humblotii var. schlechteri (H.Perrier) Bosser, Adansonia, n.s., 11: 526 (1971).
Gastrorchis humblotii var. rubra (Bosser) Bosser & P.J.Cribb in D.J.Du Puy & al., Orchids Madagascar: 145 (1999).
Gastrorchis humblotii var. schlechteri (H.Perrier) Senghas ex Bosser & P.J.Cribb in D.J.Du Puy & al., Orchids Madagascar: 145 (1999).
Description:
Plants 45-80 cm tall, pseudobulbs with 2-4 petiolate leaves (petiole 13-20 mm) elliptical-lanceolate or oval lanceolate (25-40 x 6-10 cm), plicate-veined, acute and attenuate toward both ends. Scape 60- 90 cm tall; cluster loosely 12-15 flowered: bracts herbaceous, green, narrow, lanceolate, obtuse and with the veins less numerous, generally slightly longer than the pedicel. Sepals red, oval (3-3.2 cm x 2 cm), shortly, apiculate. Petals similar, but smaller (2.5-2.8 x 1.5-1.8 cm). Labellum (3 x 3 cm) lateral lobes thick and clear red; median deeper, slightly longer than wide, larger than the 2 laterals together: with a large number of hairs at the base of the labellum: V shaped callus 8 mm tall elongated in front by a single flat keel. Column curved, 2.2cm long. Rostellum longer than wide on top. Anther bearing several hairs, basally, elongated in front by an attenuate then truncate rostrum. Pedicel 3-3.2 cm long.
Habitat:
This species grows terrestrially in very dense shade in the wet semi deciduous tropical forest. it grows at elevations of up to 5,000 plus feet and endures temperatures in the 40's during the dry season. The Mandraka is mentioned as a specific locality.
Cultivation:
Read more of cultivation of Calanthe humblotii (Rchb.f.) M.W.Chase, Christenh. & Schuit.,
Notes:
Most hobbyists think of Phaius as a large "tropical foliage" plant. However, the Madagascan Phaius, or Gastrorchis, are very moderate in size. The flowers are showy and colorful, and continue to open for a period of 4 weeks or more. This species deserves a much larger place in modern collections.
Distribution:
Madagascar.
References:
Flora of Madagascar: vascular plants: 49th family, Orchids / by H. Perrier de La Bathie; published under the auspices of the government of Madagascar and under the direction of H. Humbert; English revision and translation by Steven D. Beckman; Field Guide to the Orchids of Madagascar Cribb & Herman 2009; Orchids of Madagascar Hermans, Du Puy, Cribb & Bosser 2007; An Introduction to the Angraecoid Orchids of Madagascar Hillerman & Holst 1986; Expansion of Calanthe to include the species of Cephalantheropsis, Gastrorchis and Phaius (Collabieae; Orchidaceae), Vol. 472 No. 2: 23 November 2020 Phytotaxa; POWO (2022). "Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://www.plantsoftheworldonline.org/ Retrieved 18 November 2022."
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Photograph© Lourens Grobler. Image used with kind permission.	Photograph© Lourens Grobler. Image used with kind permission.	Photograph© Lourens Grobler. Image used with kind permission.	Photograph© Lourens Grobler. Image used with kind permission.