Aerangis stelligera Summerh., Kew Bull. 8: 589 (1953 publ. 1954).
Description:
Stem woody, horizontal or pendent, up to 5 cm long, bearing numerous roots 2-3 mm diam. Leaves 3-5, distichous, oblanceolate or oblong- lanceolate with a sheathing base and unequally bilobed apex, the lobes acute, the longer 5-10 mm long, leathery in texture and with a clearly reticulate venation in the dry state, 7-15 cm long, 1l5-4 cm wide. Inflorescences pendent, 10-25 cm long, bearing 3-6 large white flowers; peduncle slender, 5-10 cm long, 1-2 mm diam. bearing few subacute sheaths 5-10 mm long; rhachis slender, slightly zigzag, terete; bracts ovate, subacute or obtuse, 5-10 mm long. Flowers 2-4 cm apart, star-shaped, white; pedicel with the ovary 3-6 cm long. All the tepals spreading or becoming reflexed; dorsal sepal lanceolate, acuminate, 40-50 x 7 mm below the middle; lateral sepals similar but slightly longer and narrower; petals narrowly lanceolate, pointed, 37-40 x 4-5 mm. Lip similar to the tepals, narrowly lanceolate and almost caudate-acuminate, up to 40 x 4-5-5 mm; spur narrowly cylindrical, slightly inflated in the apical third but narrowing again towards the tip, 20-24 cm long. Column 10-12-5 mm long, somewhat inflated at the apex; pollinia ellipsoid, 2 mm long.
Habitat:
Undergrowth of very shady forests; 400-1100 m.
Notes:
This species possesses the largest flowers in the genus. It is clearly related to both the preceding, A. brachycarpa, and the following, A. megaphylla. It differs from the former by its much more slender roots, differently shaped leaves, and larger flowers with a distinctly longer column. From A. megaphylla it also differs by its larger flowers, with the spur almost twice as long, and by its smaller leaves. Both A. megaphylla and A. stelligera have much more slender roots (only 2-3 mm diam.) than any of the other large species with long-spurred flowers.
This is possibly because these are the only two species in this group that are found in a constantly humid environment. All the others occur in areas with a pronounced dry season, so that their roots need a thick cortex to make use of whatever moisture, in the form of rain or dew, is available.
Cultivation:
As given for the genus.
Distribution:
WC. Trop. Africa
References:
African Orchids in cultivationa and the wild La Croix 1997; 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. 20.01-2017; http://apps.kew.org/wcsp/
Images:
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