AFRICAN

ORCHIDS

Platycoryne crocea Rolfe in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 7: 257 (1898).
Homotypic Synonyms:

Habenaria crocea Schweinf. ex Rchb.f., Otia Bot. Hamburg.: 57 (1878), nom. illeg.
Heterotypic Synonyms:
Habenaria elegantula Kraenzl., Bot. Jahrb. Syst. 51: 376 (1914).
Habenaria ochrantha Schltr., Bot. Jahrb. Syst. 53: 494 (1915).
Habenaria montis-elgon Schltr., Notizbl. Bot. Gart. Berlin-Dahlem 8: 225 (1922).
Platycoryne montis-elgon (Schltr.) Summerh., Bull. Misc. Inform. Kew 1932: 508 (1932).
Platycoryne elegantula (Kraenzl.) Summerh. in J.Hutchinson & J.M.Dalziel, Fl. W. Trop. Afr. 2: 414 (1936).
Platycoryne ochrantha (Schltr.) Summerh., Kew Bull. 2: 125 (1947 publ. 1948).
Platycoryne heterophylla Summerh., Kew Bull. 13: 69 (1958).
Platycoryne crocea subsp. elegantula (Kraenzl.) Summerh., Kew Bull. 17: 532 (1964).
Platycoryne crocea subsp. montis-elgon (Schltr.) Summerh., Kew Bull. 17: 533 (1964).
Platycoryne crocea subsp. ochrantha (Schltr.) Summerh., Kew Bull. 17: 533 (1964).
Description:

Slender terrestrial herb 12–45 cm tall; tubers 8–18 × 5–10 mm, ellipsoid to globose, densely tomentose. Leaves 5–16, the lowermost 3–9 forming a basal tuft, spreading; the rest spaced along the stem, becoming bract-like. Largest leaf 1.5–6 cm long, 2–8 mm wide, linear or linear-lanceolate. Inflorescence compact, up to c. 3 cm long, densely 1–6(9)-flowered. Flowers yellow-orange to deep-orange, suberect. Ovary and pedicel 14–20 mm long, arching; bracts 7–18 mm long. Dorsal sepal erect, 6.5–12 × 3.5–9.5 mm, broadly ovate, very acute, the tip often slightly reflexed, convex; lateral sepals deflexed, 4.5–11.5 × 2–3.5 mm, obliquely lanceolate, acute. Petals erect, 4.5–11 × 1.5–3 mm, curved lanceolate, adnate to dorsal sepal.Lip 5–12 mm long with tooth-like lobes 1–2 mm long at base; mid-lobe 2 mm wide, ligulate, obtuse, fleshy; spur 9–15 mm long, pendent or slightly incurved. Anther 2.5–4.5 mm high, erect, obtuse or apiculate; canals 1–2.5 mm long, porrect. Stigmatic arms 1.5–3 mm long, clavate, horizontal or decurved. Rostellum erect, mid-lobe 1–2.5 mm long, triangular, acute, the side lobes shorter and truncate.
Notes:

Summerhayes in describing Platycoryne heterophylla differentiated it from Platycoryne. crocea by its larger rostellum mid-lobe and by its relatively broad basal leaves and much narrower cauline leaves. However, all the measurements given fall within the range recognised for Platycoryne crocea.
Habitat:

Brachystegia woodland on stony soil, pebbly grassland 900–1350 m.
Distribution:

Cameroon to Ethiopia and Zimbabwe

Images:
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Botanical Drawing / Herbarium
Platycorynecrocea
Photograph copyright Swiss Orchid Foundation at the Herbarium Jany Renz Image used with kind permission.