The crustose lichen genus Maronea A. Massal (Fuscideaceae) comprises about 12 species worldwide (Kantvilas 2001, 2004). The easily recognized, diagnostic features of this group of lichens are the lecanorine apothecia, Teloschistes-type ascus, and numerous spores per ascus, and these have contributed to a very stable generic concept over the years. As in many genera of lichenized fungi, however, differing species concepts have led to confusion over how many taxa are recognized. Many species, and varieties and forms of Maronea that were described on the basis of minor morphological features have since been synonymized (e.g. Harris 2006; Magnusson 1934).