Sobralia quadricolor Endrés & Rchb. f. ex Szlach., Kolan. & Baranow sp. nova (Orchidaceae) is described and illustrated. It was discovered by A. R. Endrés and H. G. Reichenbach, but they did not publish the description but just attached a note and illustration to the type specimen. Based on our observations and on the documentation prepared by Endrés and Reichenbach, we here describe S. quadricolor as a new species to validate the name. It is a member of the Sobralia-leucoxantha complex, resembling especially S. blancoi, but differs in the shape of the staminodes and in the colour of the lip.