Porpax leedalii (P.J.Cribb) Schuit., Y.P.Ng & H.A.Pedersen, Bot. J. Linn. Soc. 186: 200 (2018).
Homotypic Names:

Stolzia leedalii P.J.Cribb, Kew Bull. 34: 327 (1979).
A small epiphytic herb to ± 8 cm. tall. Pseudobulbs 1-leafed, approximate, subspherical, slightly compressed dorsiventrally, 0.5-1.1 cm. long, 0.6-1.2 cm. diameter. Leaf erect, linear or linear-lanceolate, obtuse, 2.5-7 cm. long, 0.3-0.4 cm. broad, articulated 0.6-1 cm. above apex of pseudobulb. Inflorescence erect, 2.4-4 cm. long, 1-2-flowered; peduncle very slender, wiry; bracts ovate, acute, 2 mm. long. Flowers large for genus, brown. Sepals fleshy, basally connate; dorsal sepal ovate, acute, 8.5 cm. long, 4.5 mm. broad; lateral sepals obliquely ovate, acute, 7.5 mm. long. 4.5 mm. broad, forming with the column-foot an obtuse mentum 3 mm. long. Petals small, concave in apical part, oblong, subacute, 5 mm. long, 2 mm. broad. Lip conduplicate, ovate, obtuse or rounded at apex, 4 mm. long, 2.5 mm. broad; disc verrucose, with a transverse basal callus. Column very short, fleshy, 0.6 mm. long; column-foot 3 mm. long; anther subrectangular, papillose at base.
Epiphytic on vertical trunks of trees in montane riverine forest; 1800-1950 m.
Porpax leedalii is a distinctive species in the genus. It is most closely allied to Porpax angustifolia (Mansf.) Schuit., Y.P.Ng & H.A.Pedersen but is readily distinguished by its larger size, its one leaved pseudobulbs and its large chocolate-coloured flowers.
SW. Tanzania
Kew Bull. 34: 327 (1979); Flora of Tropical East Africa: Orchidaceae, Part 2
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