Diversity and distribution of lichens from the Cerro Duida and adjacent areas, Alto Orinoco, Amazonas, Venezuela

Increasing temperature and changing land-use in the Guayana Shield and Amazonia result in an accelerated decline of sensitive lichen populations. Monitoring of these populations by biological plot inventories in particularly vulnerable sites is urgently needed. In order to know the diversity and distribution of lichen species at the Alto Orinoco, Parque Nacional Duida-Marahuaca and nearby areas from Amazonas state, Venezuela, lichens were sampled during four expeditions in more than 40 plots located from 200 m (premontane forest) to more than 1500 m elevation (altotepuyana vegetation). Additional data were obtained from literature and herbaria. Our assessment, although incomplete, revealed 205 described species, 150 undescribed species, 84 genera and 27 families. Among the described species 162 were observed in the basimontane vegetation, 38 in the montane vegetation, 24 in the altotepuyana vegetation, while 20 appear to be endemic to the study area. Sixty-nine species are new records for the Cerro Duida. A checklist with taxonomic and ecological data is presented. Five new species and one new variety are described: Cladonia duidana V.Marcano & A.Morales sp. nov. (Cladoniaceae), Pertusaria orinoquensis V.Marcano sp. nov., Sticta kunuhana V.Marcano sp. nov. (Lobariaceae), S. spruceana V.Marcano sp. nov. (Lobariaceae), Xanthoparmelia esmeraldensis V.Marcano & A.Morales sp. nov. (Parmeliaceae), and Lepraria arbuscula (Nyl.) Lendemer & Hodk. var. fumarprotocetrarica V.Marcano var. nov.