ASCOMYCOTA | LECANOROMYCETES > LECANORALES > Lecanoraceae

Genus Lecidella, diminutive of Lecidea

Common name:             Members of the genus collectively known as 'disc lichens'

Synonyms:                      Lecidea stigmatea

Habitat:                          Urban (for this entry)

Substrata:                      Rock

Growth form:                 Saxicolous

Thallus: Crustose

Apothecia:                     Lecideine

BLS identity rating: Graded 2/5 (visual identification relatively easy with care)

Thallus variable, often in round patches, areolate and/or faintly cracked, sometimes slightly course and verrucose especially towards the centre, other times almost evanescent; whitish to pale greyish to beige, becoming stained green or brown, even rust-red or black; apothecia to 1.5mm dia., mainly flat, occasionally slightly convex, blue-black, indigo to green black with glossy margins, colourless within, exciple distinct and well-developed when young, later becoming excluded.

Lecidella stigmatea is a common and widespread species found in a range of habitats on weakly calcareous and base-rich siliceous rocks, cement and mortar; in urban locations it's a pioneer coloniser of walls and paths.