Twenty-three species of epiphytic Caloplaca are recognized in India, of which Caloplaca himalayana Joshi, Y. & Upreti, characterized by thin, continuous, yellowish thallus, numerous ferruginous-red to brownish red, flat to subconvex apothecia with a persistent proper margin and lignicolous habitat, is described here as a new species. Because of the ferruginous coloured apothecial disc, the new species is provisionally placed in the ferruginea group until a taxonomic treatment of the whole group has been carried out. The ferruginea group is characterized by a whitish to grey (rarely yellowish) crustose thallus, a ferruginous to rarely blackish apothecial disc, biatorine to lecanorine exciple, thick-walled spore septa and the chemosyndrome C. The taxonomic affinities of the new taxa with several other taxa, including species of ferruginea group, are discussed. Two new records for India are also recorded: Caloplaca alnetorum Giralt, Nimis & Poelt and C. crocea (Kremp.) Hafellner & Poelt. A key to all the corticolous Caloplaca species occurring in the Indian subcontinent is also provided.
