Aerangis calantha (Schltr.) Schltr., Beih. Bot. Centralbl. 36(2): 155 (1918).
Homotypic Synonyms:
Angraecum calanthum Schltr., Bot. Jahrb. Syst. 38: 20 (1905).
Heterotypic Synonyms:
Angraecum roseocalcaratum De Wild., Bull. Jard. Bot. État 5: 190 (1916).
Angraecum sankuruense De Wild., Bull. Jard. Bot. État 5: 190 (1916).
Aerangis roseocalcarata (De Wild.) Schltr., Beih. Bot. Centralbl. 36(2): 120 (1918).
Aerangis sankuruensis (De Wild.) Schltr., Beih. Bot. Centralbl. 36(2): 120 (1918).
Aerangis parvula Schltr., Notizbl. Bot. Gart. Berlin-Dahlem 7: 329 (1919).
Description:
Stem very short, woody, up to 3 cm long, 3 mm diam., bearing smooth slender greyish roots 1-1.5 mm wide in the lower part. Leaves 2-6, alternate, usually distichous, closely overlapping on the stem, linear, often falcate, somewhat attenuated towards the base, unequally bilobed at the apex, the lobes acute, 0-3 mm long, the shorter one sometimes absent, margins entire, thin or somewhat fleshy, dark green with few black dots, 3-8 cm long, 4-8 mm broad. Inflorescences arising below the leaves or in the leaf axils, often from the same site as in preceding years, spreading or pendent, up to 11 cm long bearing 2-5(-8) flowers; peduncle terete up to 3 cm long, 2 mm diam., bearing 1-3 tubular sheaths; rhachis straight; bracts broadly triangular 1-3 mm long. Flowers held erect, second, 1-1.5 cm apart, white, the spur often pink; pedicel with ovary pinkish-brown, 12-17 mm long. Dorsal sepal erect, oblong-lanceolate, subacute, 7-12 x 2-3-5 mm; lateral sepals similar, slightly longer and narrower, projecting forwards. Petals spreading or slightly reflexed, linear-oblong, subacute, 7-10 x 2-2-5 mm. Lip oblong- lanceolate, apiculate, 7-10 x 2-3-5 mm; spur slender, gradually tapering to the pointed tip which is often curved or hooked forwards in the lower 5-10 mm, 2-5-4 cm long. Column short and thick, 1.5-2 mm long; androcilnium sloping, anther cap beaked; rostellum curving downwards and then forwards; pollinia reniform; stipes slender attached to the centre of the viscidium; viscidium slipper-shaped, fitting over the tip of the rostellum; stigmatic surface oblong, large, occupying most of the front of the column. Fruit a cylindrical capsule, to 5 cm long, 5 mm diam.
Habitat:
In deep shade, usually on small twigs and branches, at low levels and in the canopy, found in primary forest and on plantation trees such as coffee, cocoa and orange where these have replaced forest; 1000- 1650 m.
Cultivation:
Probably requires intermediate temperatures, with shade and high humidity. With its fine roots, it should be one of those species that will do well in a pot.
Distribution:
Ivory Coast to Angola and Tanzania
References:
Flora of Tropical East Africa Orchidaceae Part 3 Cribb 1989; Orchids of Kenya Stewart 1996; Angraecoid Orchids Stewart, Hermans and Campbell 2007, Stewart, J. (1979). Stewart, J. (1979). A Revision of the African Species of Aerangis (Orchidaceae) Kew Bulletin, Vol. 34, No. 2 (1979), pp. 239-319; WCSP (2017). 'World Checklist of Selected Plant Families. 18.01-2017; http://apps.kew.org/wcsp/
Images:
Click on each image to see a larger version.
| In culture | In culture | Flower details |
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| Photograph Gilles Grunenwald. Image used with kind permission. | Photograph Gilles Grunenwald. Image used with kind permission. | Photograph Gilles Grunenwald. Image used with kind permission. |
