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

Stolzia compacta subsp. iringana P.J.Cribb, Kew Bull. 33: 83 (1978).
Differs from other subspp. in its dwarf habit less than 4 cm. high, smaller pseudobulbs ± 0.5 cm. in diameter, smaller leaves with a slender petiole and smaller butterscotch-yellow flowers.
Epiphyte in dwarf montane forest; 1700-2100 m.
Only subsp. iringana Cribb occurs in the Flora area; this is a much smaller plant than the other subspecies reaching scarcely 3.5 cm. tall. It has chains of small pseudobulbs to 0.5 cm. tall each bearing a single petiolate erect leaf and smaller solitary sessile butterscotch-yellow flowers. Subsp. compacta is a much larger plant (often three or four times larger) with yellow flowers whilst subsp. purpurata is almost as large and has purple flowers.
SW. Tanzania
Flora of Tropical East Africa: Orchidaceae, Part 2
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