Loxospora chloropolia

Thallus crustose, grey, matt or more often shiny, thin, continuous, slightly folded, cracked to cracked-areolate; areoles flat or rarely convex, not constricted at the base. Soralia whitish to greenish-grey, flat or more often convex, rounded or irregular, mostly discrete and separated, bursting from flat parts of thallus or from areoles, sometimes crowded and the neighbouring soralia more or less fused. Soredia to 50 μm diam., often in consoredia to 100 μm diam. Apothecia very rare, to 1.2 mm diam.; thalline margin present, not or partly to completely sorediate; disc reddish brown, thinly white-pruinose; hymenium to 100 μm high; Epithecium straw-brown (K+ pale reddish-brown), with dense granules dissolving in K. Paraphyses not capitate, sometimes anastomosing. Asci 8-spored, with a uniformly KI+ blue apical dome. Ascospores 0–3 (–5)-septate, helically coiled in asci, colourless, fusiform, curved, 35–48 × 5–7 μm. Pycnidia not known. Chemistry: thamnolic acid (major), elatinic acid (minor, trace or absent) and squamatic acid (trace or absent). Cortex, apothecial section, soralia and medulla K+ lemon-yellow, Pd+ yellow to orange, UV–.

Only recently separated from Loxospora elatina s. str. Well developed specimens lacking any tubercles and with the soralia mostly discrete and separated and retaining their identity even where crowded and partly fused are readily field separable from L. elatina s. str. Rare anomalous specimens of Loxospora chloropolia can have tubercles. In this case the soralia on these do not fully coalesce, while those on L. elatina s. str. do fully coalesce at least on part of the thallus, but sequencing is advised to confirm L. elatina s. str. in all cases. 

The K+ immediately bright yellow, soft soralia distinguishes L. chloropolia from similar species (apart from L. elatina), e.g. Biatora chrysantha, Lecanora alboflavida, Mycoblastus caesius, Mycobilimbia epixanthoides and Varicellaria hemisphaerica.