Synonyms: Caloplaca pyrithromoides (Nyl.) C.W. Dodge; Chrysomma pyrithromoides (Nyl.) M. Choisy & Werner; Lecanora pyracea f. pyrithromoides Nyl.
Distribution: N - Lig. C - Tosc. S - Cal (Herb. Vondrák 10844).
Description: Thallus crustose, thinly episubstratic, pale grey, continuous to rimose. Apothecia biatorine, 0.3-1.5 mm across, usually crowded and sometimes deformed by mutual compression, with a flat to convex, dark reddish brown disc tending to turn dark red to black in older apothecia, the disc contrasting with the margin, which remains red. Epithecium brownish orange, K+ red; hymenium and hypothecium colourless. Asci 8-spored, clavate, Teloschistes-type. Ascospores 1-septate, polarilocular, hyaline, narrowly ellipsoid, 12-20 x 5-8 µm, the septum 2-4 µm thick. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-; apothecial disc K+ red. Chemistry: apothecia with chemosyndrome C2 of Søchting (1997): absence of parietin and fragilin and traces of citreorosein andemodinal.
Note: on schists in open habitats, on dry surfaces with a short water flow after rain; poorly understood, but probably a good species, known from Italy, France, and the Iberian Peninsula. The type specimen (PRA-V 03097; syntype?) was morphologically appraised and belongs to Rufoplaca (Vondrák in litt.).