Chauliodon deflexicalcaratum (De Wild.) L.Jonss., Bot. Not. 132: 381 (1979).
Angraecum deflexicalcaratum De Wild., Bull. Jard. Bot. État Bruxelles 5: 185 (1916).
Gussonea deflexicalcarata (De Wild.) Schltr., Beih. Bot. Centralbl. 36(2): 90 (1918).
Microcoelia deflexicalcarata (De Wild.) Summerh., Bot. Mus. Leafl. 11: 152 (1943).
Chauliodon buntingii Summerh., Bot. Mus. Leafl. 11: 164 (1943).
Plant small with a short stem to 2 cm long and many elongated roots. Leaves absent. Inflorescences slender, usually 15-25 cm long but sometimes up to 60 cm long, many-flowered; bracts very small; pedicel with ovary slender, ca. 1 cm long. Flowers pinkish brown or white tinged with brown, 7-8 mm apart; dorsal sepal concave, oblanceolate, apiculate, 3.5-4 mm long, 2-2.5 mm wide; lateral sepals longer and wider in the upper part, almost L-shaped, 5-6 mm long, 2.5 mm wide; petals narrowly suboval, acuminate, 3-4 mm long, 1 mm wide; lip very short and acute, supporting a tooth-like, erect callus ca. 2 mm tall just in front of the spur opening; spur 3-3.5 mm wide and cupshaped at the mouth, narrowing to just beyond the middle where it abruptly curves forward, the apical part slightly swollen, in total 12-14 mm long.
This very remarkable plant was unfortunately overlooked when the Flora of Vest Tropical Africa was prepared. The general organization indicates a relationship to Microcoelia Lindl., especially the leafless habit, very short stems, adnation of the base of the pedicel to the rhachis, column structure and common stipes to the pollinium. The distinctive features are the lip lamina reduced to a tooth-like point and the tall erect acute callus placed just in front of the spur mouth; the generic name is given in allusion to this. This callus is keeled on the outside and hollow towards the column the two sides diverging and making the callus V-shaped in transverse section. The stipes of the pollinarium is broadened in the upper half to form a flattened plate which is wrapped around the greater part of the pollinia; these arise some distance below the apex on a slightly less sloping or horizontal portion of the widened area.
Epiphyte on trees in rain forest and on well-shaded shrubs at forest margins; flowering in July and January.
As given for the genus, hot growing epiphyte.
W. & WC. Trop. Africa
Encyclopedia of Cultivated Orchids Hawkes 1965; Angraeciod Orchids Stewart, Hermans and Campbell 2006; WCSP (2017). 'World Checklist of Selected Plant Families. 12.03-2017; http://apps.kew.org/wcsp/
Click on each image to see a larger version.