A taxonomic treatment of the genera included in Catapyrenium s. lat. in the Iberian Peninsula and the Balearic Islands is provided, based on study of c. 2000 specimens from both herbaria and fresh material collected by the authors from 2005 to 2009 in numerous localities.

A total of 33 species belonging to six of the eight genera included in Catapyrenium s. lat. are present in the region, which correspond to c. 80% of species from Europe. The genera are Anthracocarpon Breuss, Catapyrenium Flot. (Catapyrenium s. str.), Heteroplacidium Breuss, Involucropyrenium Breuss, Neocatapyrenium H. Harada and Placidium A. Massal. The genus Neocatapyrenium is reported for the first time from this region. Clavascidium liratum, the only representative of the genus Clavascidium in the region, has been reduced to synonymy with Anthracocarpon virescens.

Heteroplacidium acervatum, H. congestum and Neocatapyrenium cladonioideum are new to Europe. Involucropyrenium pusillum, only previously known from Austria, I. waltheri, an arctic-alpine species, and Neocatapyrenium latzelii, known from Croatia and Greece, are cited for the first time in the Iberian Peninsula. Placidium subrufescens and P. tenellum, two mainly Mediterranean species, are also new records from the Iberian Peninsula. Placidium boccanum is here for the first time cited in Spain, and Anthracocarpon virescens, Heteroplacidium contumescens, Placidium imbecillum and P. michelii are new to Portugal. Most of the remaining species showed a considerable expansion of their known ranges. Placidium pyrenaicum is reduced to synonymy with P. velebiticum.

Keys to genera and species occurring in the Iberian Peninsula and the Balearic Islands are presented.