Platycoryne isoetifolia P.J.Cribb, Kew Bull. 32: 141 (1977).
Platycoryne robynsiana Geerinck, Bull. Jard. Bot. Natl. Belg. 52: 345 (1982).
Slender terrestrial herb 20–30 cm tall; tubers c. 10 × 7 mm, ovoid, tomentose, up to 5 cm below ground on the end of a stalk. Leaves 6–10, with up to 9 in a basal tuft and 1–2 cauline leaves. Basal leaves 12–18 mm long and 1–2 mm wide, narrowly lanceolate; cauline leaves c. 10 mm long. Inflorescence up to 10 cm long, laxly 1–7-flowered.Flowers green or yellow-green, suberect. Pedicel c. 10 mm long, ovary c. 10 mm long, making an angle of almost 90° with the pedicel. Bracts c. 7 mm long. Dorsal sepal erect, 1.5 × 2 mm, ovate, convex; lateral sepals 4 × 1.5 mm, lanceolate, falcate, adnate to dorsal sepal. Lip 6 mm long, 3-lobed at base; mid-lobe 6 × 2 mm, ligulate or slightly spathulate, obtuse; side lobes 3 × 1 mm, ligulate, obtuse; spur 15 mm long, pendent, slender but swollen at apex. Anther 1 mm high; canals very short, incurved. Stigmatic arms 1 mm long, truncate. Rostellum mid-lobe acute, concave, lying in front of anther loculi; side lobes incurved.
In wet or dry dambo.
Platycoryne isoetifolia is related to Platycoryne brevirostris Summerh. but it differs in being a more slender plant with shorter, needle-like leaves and smaller flowers with a lip trilobed at the base rather than in the middle. The yellowish-green flowers of Platycoryne isoetifolia resemble those of Habenaria filicornis (Thonn.) Lindl. with a distinctly trilobed lip but the rostellum mid- lobe is concave and placed in front of the anther loculi as in other Platycoryne species.
Not in cultivation.
Endemic to Zambia. Alt. ca. 1350 m.
Orchidaceae of West-central Africa, vol. 1, Gdansk University Press Gdansk 2010; New Orchids from South Central Africa, Kew Bulletin, Vol. 32, No. 1 (1977)
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