A total of 224 species of corticolous macro lichens are recorded from low montane rainforests and moist woodlands in the West Usambara Mountains, the Nguru Mountains, the Uzungwa Mountains, thePoroto Mountains, and theRungwevolcano in eastern Tanzania. Local distribution data are provided. The new species Hypotrachyna olivetorica Krog, Parmotrema iringense Krog, and Ramalina dissimilis Krog are described. Heterodermia dissecta, H. jragi/issima, Parmelinopsis expallida, and Phyllopsora kiiensis are reported as new to Africa.
Cetrariastrum ajricanum, Pannaria santessonii, Parmotrema degelianum, P.fragilescens, P. hicksii, P. iringense, P. laciniatulum, Ramalina dissimilis, R. pocsii, and Usnea antiqua are at present known only from eastern Tanzania. Some of them may possibly belong to an endemic element in the montane lichen flora of the country.
Hypotrachyna olivetorica, Lobaria holstiana, Phyllopsora africana, P. dolichospora, and P. mauritiana are known only from eastern Tanzania and the Mascarenes.