Thallus areolate or coarsely rimose-cracked, thick, yellow-brown to brown-grey, thickly and densely covered in flattened or spherical blastidia, 45-65 μm diam., forming chains. Cortical layer ca 40 µm thick, composed of tightly packed hyaline hyphae. Photobiont chlorococcoid.
Anamorph: not known.
Teleomorph: ascomata apothecia, 500-1200 µm diam., sessile, sometimes constricted at the base, sometimes partially obscured by blastidia, single or in small clusters, often deformed. Disc red-brown to black, plane to shallowly convex, sometimes densely grey-pruinose. Thalline margin well-developed, brown-grey, irregular, swollen, irregularly cracked to incomplete and partially hidden, surface densely and minutely granular with blastidia. Hymenium 60-70 µm tall, surrounded by a sterile hyphal layer to 25 µm wide at the upper surface. Epithecium reddish-brown, densely granular. Hypothecium colourless or pale. Interascal tissue of paraphyses, short-celled towards the apices, sometimes weakly branched at the top, I/KI+ blue, the apical cells swollen, colourless to weakly reddish-brown, 3-5 µm diam. Ascospores 19-25 × 4-4.5 μm, narrowly ellipsoidal, sometimes curved, 3-septate, hyaline, smooth- and thin-walled, without a gelatinous sheath or perispore.
Chemistry: no information available.
Listed as Extinct by Woods & Coppins (2012), but rediscovered in a single locality in 2013. Further surveys would be highly desirable. Possibly endemic to Great Britain (see below).
Similar to Lecania erysibe but that species has less well-developed blastidia (usually restricted to thalline margins), and smaller 1- rather than 3-septate ascospores. The accounts of L. coeruleorubella by van den Boom (1992) from Luxemburg and by Nash et al. (2001) from Arizona appear to apply to a different species within the L. erysibe aggregate with much smaller ascospores.
In GB&I, recorded from its original collection sites in VC62 NE Yorkshire [now presumed extinct], and a modern record from VC20 Hertfordshire.
Recently reported on limestone and mortar courses of a church wall (in various aspects). The original description only refers to "old walls &"