Description of a new species of non – lichenized lichenicolous fungus, Zwackhiomyces lecaniae D. Gonnet, O. Gonnet & Cl. Roux, parasite on the thallus and apothecia of Lecania olivacella (note on the latter). Comparison of the new species with other known Zwackhiomyces. Corrigendum to the I reactions of Zwackhiomyces indicated by Poumarat et al. (2022). Key to the species of Zwackhiomyces. France. Zwackhiomyces lecaniae D.Gonnet, O.Gonnet & Cl.Roux (on Lecania olivacella from France). Includes key to Zwackhiomyces