Descriptions and a key for identification of licheniocolus Arthonia sp
ecies with red to purple pigments reacting with K are provided. The pr
eviously reported species, A. cryptotheciae and A. mazosiicola (as A.
mazosiae), are here validly described, and A. haematostigma, A. tavare
sii and A. destruens var. nana are new to science. The genus Helicobol
omyces is introduced with the type species H. lichenicola, being based
on the anamorph of A. cinnabarinula.