Porpax compacta (P.J.Cribb) Schuit., Y.P.Ng & H.A.Pedersen, Bot. J. Linn. Soc. 186: 199 (2018).
Homotypic Names:

Stolzia compacta P.J.Cribb, Kew Bull. 32: 159 (1977).
A small repent epiphytic herb to 9 cm. high. Pseudobulbs fleshy, borne in chains, ovoid-fusiform to compressed-pyriform, 1.5 cm. long, 0.9 cm. high, 1-leafed at apex. Leaves thin in texture, oblanceolate, to 9 cm. long and 1.2 cm. wide, rounded and minutely bilobed at apex, base attenuate, articulated to a short 0.5 cm. long leaf-base. Inflorescence 1-flowered, very much shorter than the leaf. Flower pale to butterscotch-yellow or purple, fleshy. Dorsal sepal lanceolate, acuminate, 7-9.5 mm. long, 2.3-3.5 mm. broad, with ± reflexed margins; lateral sepals fused in basal half and to column foot to form an obscurely saccate mentum ± 2 mm. long. Petals linear-lanceolate, acute, 4-5.5 mm. long, 1-1.5 mm. broad. Lip narrowly ovate to elliptic-ovate, rounded at apex, deeply sulcate in basal half, 3.5-4 mm. long, 2-2.5 mm. broad; callus obscure, basal, small, warty. Column truncate, 0.6-0.8 mm. long; column-foot incurved, 2-3 mm. long.
Epiphytic on mossy branches in montane forest, 1600-2350 m.
Porpax compacta (P.J.Cribb) Schuit., Y.P.Ng & H.A.Pedersen may be distinguished from Porpax oligantha (Mansf.) Schuit., Y.P.Ng & H.A.Pedersen by its ovoid, unifoliate slightly compressed pseudobulbs which are closely spaced, its obovate petiolate leaf and its single-flowered inflorescence. Porpax repens (Rolfe) Schuit., Y.P.Ng & H.A.Pedersen also has a single-flowered inflorescence but each pseudobulb is bifoliate and the leaves are ovate. Porpax compacta (P.J.Cribb) Schuit., Y.P.Ng & H.A.Pedersen has yellow or yellowish-green flowers but collections have been made of a closely related purple flowered species in Rhodesia.
Potted in a standard bark mix, or mounted, but the humidity must be kept high, particularly in the growing season. Intermediate temperatures and heavy shade.
SW. Tanzania to E. Zimbabwe
New Orchids from South Central Africa, Kew Bulletin, Vol. 32, No. 1 (1977)
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