Chaenotheca stemonea (Ach.) Müll. Arg.

Chaenotheca stemonea is recognizable by its finely farinose (leprose), yellowish or bluish light-green thallus which, due to the presence of barbatic and obtusatic acids, turns yellow-orange in the reaction with Pd. The species' typical habitats are shaded and rain-protected patches of acidic tree bark, such as on tree bases or in deep crevices. The lichen is most often found on spruce and oak trees. Rarely, it also grows on wood of stumps and snags. It occurs in various forest types, from lowland oak forests and floodplain forests to mountain spruce forests. Generally, the lichen prefers old natural forest stands. It is sparse in the Czech Republic and central Europe, but may be locally abundant. It is probably a partially overlooked lichen due to its usually hidden occurrence and frequent absence of fruiting bodies.

Ascomycota → Lichinomycetes → Coniocybales → Coniocybaceae → Chaenotheca