The trumpet lichen (Cladonia fimbriata) has two types of pale gray, greenish thallus: one primary thallus that grows flat, leaf-like and one standing up secondary thallus in trumped shape named podetia. The podetia are slim to 3 cm high; its thin, cylindrical stem suddenly opens to a 2-5 mm cup. The podetia are fully coated by granular or powdery soredia for reproduction. The inside of the cup doesn’t contain small, bright green disks as in Cladonia pyxidata, a close-by species. Small, brown coloured pycnidia can be found on the lobed edges of the cup, though not as big and visible as in Cladonia chlorophaea. To some extent, the trumps of C.fimbriata look like young yellow foots (Cantharellus lutescens).
The responsible for the green shadow of Cladonia pyxidata is the green algae Trebouxia, quite common in lichens.
Cladonia fimbriata is found mainly on decay wood as stumps of green oak, but also on the ground amongst mosses. Cladonia fimbriata is common and widespread. Often C.fimbriata, C.pyxidata & C.chlorophaea lichen species, all them with trumpet like podetia and common, are mixed up.
[photo Jordi Badia]