Aim To describe the composition, diversity and biogeographical affinities of the foliicolous lichen mycobiota in Valdivian temperate rain forest in southern South America.
Location Seven localities in Chile (IX to XI region) and Argentina (Neuquén province).
Methods Opportunistic sampling of leaf substrates, identification of taxa, and assignment to distribution types.
Results Thirty-seven species, including three lichenicolous fungi, were found in the studied collections, increasing the number of foliicolous taxa known from Valdivian temperate rain forest to 55. New records for the area include Arthonia cyanea, Byssoloma marginatum, B. subdiscordans, Fellhanera bouteillei, F. dispersa, F. subfuscatula, Gyalectidium caucasicum, G. ciliatum, Logilvia gilva, Porina thaxteri, Strigula nitidula and the lichenicolous A. microsticta, Helicobolomyces lichenicola and Opegrapha sipmanii. Seven taxa are described as new: Enterographa falcata, Gyalectidium chilense, G. plicatum, Gyalideopsis choshuencensis, Porina fulvelloides, Strigula wandae and Trichothelium meridionale ssp. austroamericanum.
Conclusions There are unexpected floristic affinities in the foliicolous lichen mycobiota of Valdivian temperate rain forest with those of New Zealand and Tasmania. Three typically foliicolous species clearly belong to an austral element: Caprettia setifera and Badimiella pteridophila, both known previously from New Zealand and Tasmania; and Kantvilasia hians, known already from Tasmania and Valdivian temperate rain forest. Other Southern Hemisphere lichens, such as Parmeliella nigrocincta, P. thysanota and Psoroma caliginosum, are also found commonly on leaves. On the other hand, specific affinities of the foliicolous lichen mycobiota of Valdivian temperate rain forest with the Neotropics are absent: most of the species shared between the two regions belong to a cosmopolitan-tropical or a circumpacific element. Thus far, nine taxa are endemic to Valdivia. The Valdivian temperate rain forest foliicolous lichen mycobiota is therefore regarded as one of six distinctive regions in the world.