ASCOMYCOTA | LECANOROMYCETES > TELOSCHISTALES > Teloschistaceae

Genus Caloplaca, meaning 'beautiful patches'

Common name:            -

Synonym:                    Variospora flavescens

Habitat:                         Coastal

Substrata:                     Rock

Growth form:                Saxicolous

Thallus:                  Crustose - placodioid

Apothecia:                    Lecideine

BLS identity rating:        Graded 1/5 (identification should be relatively straightforward)

Thallus normally rosette shaped, typically between 3-8cm across, colour variable from bright yellow-orange to darkish orange, frequently with a whitish ringed zone behind the lobes, the centre may be almost areolate, but often disappearing or breaking up leaving arcs; the lobes are quite long, narrow and closely appressed, contiguous to pleated, smooth to faintly rugose, convex, and with the ends only very slightly wider; apothecia can be numerous, usually clustered more towards the centre of the thallus, the discs are orange, sometimes more brown-orange towards the centre, with slightly paler margins, flat or only slightly convex, and up to 1.5mm dia.

It is very common on calcareous rocks and locally is by far the most frequently observed coastal lobate Caloplaca species, often mixed with other maritime lichens, but it's also found on sea walls and inland on cement and tombstones. In its more normal coastal habitat, it is only likely to be confused with Caloplaca thallincola, although that species occurs lower down the shore in the mesic supralittoral spray zone and, on closer inspection, has a different form, usually more circular, brighter, glossier and with longer lobes.