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 Add this item to the list  804718 Original description
Description type:Original description 
Description:Thallus grey and mat to olive-grey to brownish-grey and then somewhat glossy due to the presence of an obtecting epinecral layer, areolate, spreading, up to c. 6 cm in diam., invading Sporastatia-thalli, older thalli sometimes starting to crumble from the centre; areolae smooth or superficially somewhat subdivided, subconvex to convex, c. 0.7–1.5 mm in diam. Hypothallus indistinct.
Apothecia black, tightly adpressed or marginally attached to areoles and semiimmersed (but not aspicilioid), 0.2–0.5(–0.8) mm in diam, plane to subconvex, with persistent thin somewhat glossy margin. Excipulum externally redbrown occasionally with shades of violet, verging to olive-brown in the upper part, internally paler to subhyaline. Hypothecium hyaline (basally sometimes slightly brownish). Hymenium hyaline, 40–55 µm high, upper 10–15 µm greyish-brownish to dark olive-brown, forming an epihymenial layer; paraphyses mostly simple or with few ramifications in the upper part, c. 50 µm long and 1–2 µm thick; apical cells hardly or slightly enlarged, up to 3–4 µm in diam., embedded in pigmented gel (“Pigmenthauben-type” sensu Kilias 1981). Asci of Lecanora-type, broadly cylindrical to subclavate, 8-spored, 35–45 x 12–16(–18) µm, external ascal wall layer and tholus except the axial body I(Lugol)+ blue; ascospores hyaline, non-septate, ellipsoid, 9–11(–12) x 4.5–5.5(–6) µm, length-width-ratio c. 2–2.4.
Pycnoconidia filiform, bending or straight, 20–30(–40) x c. 1 µm.

Secondary chemistry: Cortex K-, P-, C-, medulla K+ yellow, P+ orange-red, containing miriquidic acid and stictic acid (plus accessory compounds, of which namely constictic acid is often present in detectable amounts) in the thallus (number of specimens investigated: 71).
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