Cladonia mediterranea Duvign. & des Abb.
Primary thallus evanescent, disappearing rapidly. Secondary thallus for ming erected small bushes up to 10-12 cm tall, in sparse cushions, composed of podetia, main branches widened towards the base, mostly dichotomous frequent branching in all directions, but sometimes only in the South direction, smooth cortex felt-like, whitish, white-grey, white-yellow (the most frequent) and slightly greenish due to pale green spots (when moist), unchanged when exposed to sun. Apothecia rare in our prospection area, otherwise convex and brown. C-, K-, KC+ yellow, Pd-. Photobiont : Chloroccacea. On mostly neutral well lit aerohaline heathlands since this species is thermophilic and at its Northern distribution limit in our prospection area.
Not to be confused with Cladonia portentosa that is rather close but much more common, more erect, thinner with pointed apices clearly brown-red, branching often trichotomous and podetia bases not widened, nor with Cladonia arbuscula, also trichotomous, Pd+ red, and with branches oriented in the same direction and conspicuous pointed apices brown-red.
N.B. The pictures of the Pointe de Dinan were taken in a station precisely indicated by des Abbayes and at the time constituting the northern limit of this species.