Porpax williamsonii (P.J.Cribb) Schuit., Y.P.Ng & H.A.Pedersen, Bot. J. Linn. Soc. 186: 201 (2018).
Homotypic Names:
Stolzia williamsonii P.J.Cribb, Kew Bull. 33: 88 (1978).
Description:
A dwarf creeping epiphytic herb. Pseudobulbs 2-leaved, narrowly long-clavate, horizontal, appearing rhizomatous, swollen below leaves only, 2-4 cm. long, 1 2 mm. diameter. Leaves thin-textured, spreading, obovate to elliptic-obovate, rounded a apex, shortly petiolate, 1-2 cm. long, 0.5-0.9 cm. broad, articulated 1 mm. above apex of pseudobulb. Inflorescence 1-flowered, much shorter than leaves peduncle up to 3 mm. long; bract ovate-elliptic, acute, 1.5 mm. long. Flower large for size of plant non-resupinate, red-brown. Dorsal sepal concave, narrowly oblong-elliptic, obtuse 8.5 mm. long, 3 mm. broad; lateral sepals obliquely ovate-elliptic, obtuse, united for basal one-third, 7-7.5 mm. long, 3 mm. broad; mentum saccate, 2-2 5 mm. long Petals oblong-elliptic, obtuse, papillose, 7 mm. long, 2 mm. broad Lip recurved, narrowly clawed, lanceolate-ligulate, acute or acuminate, 3 5 mm. long.
Etymology:
After Graham Williamson (1932- ), Zimbabwean dental surgeon and collector, particularly of orchids, in Zambia and Malawi. He first found and described many species and is the author of Orchids of Central Africa (1977).
Habitat:
Epiphyte in montane forest; 2150-2900 m.
Flowering time:
Feb - Mar
Distribution:
Rwanda to N. Malawi
References:
Flora of Tropical East Africa: Orchidaceae, Part 2; Cribb, P.J. (1978). A revision of Stolzia (Orchidaceae) Kew Bulletin 33(1) Page 88.; La Croix, I. et al. (1991). Orchids of Malawi A.A. Balkema, Rotterdam Page 185.; La Croix, I. & Cribb, P.J. (1995). Orchidaceae (Part 1) Flora Zambesiaca 11(1) Page 291.
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