Caloplaca ferruginea

Crustose lichen, in the center of the image. On the left we have a foliose lichen called Physcia tenella, with dark cillia, on the right another foliose lichen, probably Physcia stellaris. The apothecia are characteristically a deep red colour with a flexuose or uneven rim. The thallus is white to grey in colour and may be immersed in the substrate. Usually found on the bark (neutral to basic) of mature trees or on twigs, including hawthorn and oak. When the apothecia are cut in section there is rarely any photobiont present (in the hymenium).