Porpax Lindl., Edwards's Bot. Reg. 31(Misc.): 62 (1845).
Aggeianthus Wight, Icon. Pl. Ind. Orient. 5: 18 (1851).
Conchidium Griff., Not. Pl. Asiat. 3: 321 (1851).
Lichenora Wight, Icon. Pl. Ind. Orient. 5: t. 1738 (1851).
Alvisia Lindl., Fol. Orchid. 8: 1 (1859).
Stolzia Schltr., Bot. Jahrb. Syst. 53: 564 (1915).
Herbs, epiphytic or lithophytic, tiny, clump-forming. Pseudobulbs crowded together, flattened globose, usually wider than long, 2- or 3-leaved, covered by a sheath that disintegrates into a fine fibrous network or into radiating fibers; sheaths white, with reticulate or other veins. Leaves appearing at or after anthesis; blade elliptic, ovate, or oblong, sometimes minutely hairy on margin, apex obtuse or acute. Inflorescence 1-flowered (rarely 2- or 3-flowered), borne either from base of pseudobulb, breaking through sheath, or from apex of a developed pseudobulb; peduncle and pedicel very short, flower appearing sessile at edge or center of pseudobulb; floral bract conspicuous, enclosing lower part of flower. Flowers orange-red to deep dull red, sometimes flushed with greenish yellow. Dorsal sepal connate with lateral sepals at least at its base; lateral sepals connate nearly, or completely, to apex, forming a tube and a mentum with column foot. Petals spatulate to oblong, narrow, smaller and shorter than sepals, sometimes hairy; lip completely enclosed in tube, very small, much shorter than petals, obscurely 3-lobed, usually recurved; disk with a basal callus. Column short but distinct, with conspicuous foot; pollinia 8, waxy, in 2 groups, each group attached to a viscidium; rostellum rather large, often covering stigma entrance.
This genus of small creeping epiphytes was named in honour of Adolf Stolz, a German missionary who lived in southwest Tanzania for many years, and who made many important orchid collections around Tukuyu where he was based.
All the species of Porpax (Stolzia) are small, creeping or upright epiphytes which produce chains of small pseudobulbs that appear to creep over the surface of branches and rocks. Each pseudobulb bears one or two leathery leaves at its apex, and an inflorescence arises between them. Ten species have been described from Tanzania but only one from Kenya. It is the most widespread of all the species and is easily recognized by its single bright red or orange flower that is almost stem less and borne between the leaves. From a little distance the plants resemble a mossy carpet and are sometimes con- fused with small plants of Peperomia species when not in flower.
Small mats of the creeping stems of this orchid are not difficult to establish on a piece of bark or tree fern fibre. However, they need cool, humid conditions and are not easy to keep alive if there is continuous hot weather. They are not difficult to maintain under glass in cool conditions. They respond well to frequent misting and thrive in a shady position.
POWO (2022). "Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://www.plantsoftheworldonline.org/Retrieved 15 November 2022."
Bibliography and References:
Cribb PJ. 1978 A revision of Stolzia (Orchidaceae). Kew Bull. 33. (1): 79 - 89 (1978)
Cribb PJ. 1979 New or little known orchids from East Africa. Kew Bull. 34. (2): 321 - 340 (1979)
Cribb PJ. 1981 A new species of Stolzia (Orchidaceae) from Tanzania. Kew Bull. 36. (3): 639 - 641 (1981)
Droissart, V., Simo, M., Sonké, B., Cawoy, V. & Stévart, T. (2009) Le genre Stolzia (Orchidaceae) en Afrique centrale avec deux nouveataxons. Adansonia, sér. 3, 31(1), 25-40.
Pottinger M. 1982 African orchids. Plectrelminthus to Ypsilopus. Orchid Rev. 90. (1070): 384-385 (1982)
Stevart T, Cribb P. 2004 New species and records of Orchidaceae from Sao Tome and Principe. Kew Bull. 59. (1): 77-86 (2004)
Williamson G. 1976 Some interesting miniature Epiphytes. Orchid Rev. 84. (996)
Williamson G. 1980 Studies in Orchidaceae from South Central Africa. (Studies van Orchidaceae vanaf Suid Sentraal Afrika.) J.S. Afr. Bot. 46. (4): 329 - 342 (1980)
Phylogenetics and systematics of Eria and related genera (Orchidaceae: Podochileae), Botanical Journal of the Linnean Society, 2018, 186, 179–201.
Flora of Tropical East Africa: Orchidaceae, Part 2: Tribes Neottieae and Epidendreae, p.p.