Chiodecton epiphyllum is a lichenicolous fungus on Coenogonium flavicans and belongs in the genus Plectocarpon (Arthoniales : Roccellaceae)

The biological status of Chiodecton epiphyllum (Arthoniales: Roccellaceae), described as a foliicolous lichen from Papua New Guinea, is reassessed, based on additional material from Brazil, Costa Rica, and Papua New Guinea. The species is a lichenicolous fungus growing on the foliicolous lichen Coenogonium flavicans (Gyalectales: Gyalectaceae). Furthermore, its ascomatal anatomy and lichenicolous growth habit suggest placement in the related genus Plectocarpon, instead of Chiodecton. We therefore propose the new combination Plectocarpon epiphyllum [Bas.: Chiodecton epiphyllum]. The species is further lectotypified on its ascomata since parts of the original description which denote vegetative characteristics refer to the sterile thallus of the host lichen. (C) 2001 The British Lichen Society.