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

Bulbophyllum peperomioides Kraenzl., Bot. Jahrb. Syst. 43: 341 (1909).
Stolzia peperomioides (Kraenzl.) Summerh., Kew Bull. 8: 142 (1953).
Although it is not possible to examine the type specimen of this species, as it was destroyed during the war, there seems little doubt from the description and illustration that the species is referrer to Stolzia and not to Bulbophyllum.
Reference to the illustration of B. gracilipes King and Pantling, with which Kraenzlin compares it, shows a plant of quite different basic construction both vegetatively and florally. The view that Bulbophyllum peperomioides is really a Stolzia receives almost overwhelming support from the discovery of another very closely allied species, Stolzia diffusa Summerh., described below. This is strikingly similar to Bulbophyllum peperomioides Kraenzl. in all described and illustrated characters, while in the structure of the column, anther and pollinia it is a characteristic member of the genus Stolzia.
Kraenzlin in his description mentions that the sepals are united at the base, one of the characters of Stolzia, while he also refers to the simple ecallose labellum and the very small column. He appears to misinterpret the line of demarcation between the pseudo- bulbs and leaves, as he describes the rhizome as creeping with cylindrical one-leaved pseudobulbs 5-7 mm. long, placed at intervals of 2-4 cm.
He compares these pseudobulbs with a petiole. In Stolzia diffusa Summerh., however, the " rhizome " consists of the superposed pseudobulbs, each new one arising from just below the apex of the previous one. The single leaf is borne at the apex of the pseudobulb and has a narrow cylindrical basal part corresponding to the sheath in most. orchid leaves, above which is an articulation and then the petiole and lamina.
The illustration of Bulbophyllum peperomioides shows exactly the same type of general construction and I have little doubt that the two species agree in these features. Stolzia peperomioides, instead of possessing the single-flowered inflorescences found in Stolzia repens, Stolzia cupuligera and Stolzia diffusa, has a long peduncle bearing several flowers in the upper part. In this respect it agrees with Stolzia nyassana Schltr. and Stolzia atrorubra Mansf. which belong to the other group of the genus.
On the other hand at least one of the plants collected by Mr. and Mrs. Moreau is said by them to have constantly one-flowered inflorescences. Evidently the number of flowers in the inflorescence varies from one to several in both groups within the genus.
WC. Trop. Africa
AFRICAN ORCHIDS: XXI 143; Orchid Monographs Vol 2 - A Taxonomic Revision of the Continental African Bulbophyllinae Vermeullen 1987; A Revision of Stolzia (Orchidaceae) by P. J. Cribb, Kew Bulletin Vol. 33, No. 1 (1978), pp. 79-89 (11 pages)
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