Drei parasitische Flechten aufCaloplaca polycarpoides

Abstract

No less than 3 different parasitical lichens were found on the corticolous lichenCaloplaca polycarpoides in Afghanistan. Partly, they also grow on closely allied species of the sect.Xanthoriella. Lecania triseptata begins and ends as a typical parasite, and does not form a thallus outside of its host.L. diplococca andRinodina afghanica, both described as new species, have a similar appearance; they are parasitic in the beginning, but form their own thalli outside the host later on. The 3 species are members of the small group of parasitical lichens growing on corticolous hosts. Possibly, the slow degeneration of cortices under the arid climatical conditions, has allowed the evolution of parasitic lichens of this rare type in Central Asia.