The genus Physcia in East Africa

Abstract

Twenty‐one species of the lichen genus Physcia (s. str.) in East Africa are treated. Their morphology, chemistry, distribution, habitat and relation to other taxa are discussed. Section Atrae and five species are described as new; P. atrostriata, P. erumpens, P. krogiae, P. undulata and P. verrucosa. The structure of the lower cortex is divided into six different types and the types of soralia have been classified in two main groups with some sub‐groups.