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 Add this item to the list  830184 Original description
   
Remarks (public):Diagnosis: The species differs from Myochroidea porphyrospoda by the indistinct or endosubstratal, whitish thallus in non-sorediate parts, the scattered, effuse soralia, the absence of areoles being not completely sorediate, the apothecia being rare and poorly developed, and the strong preference for trunks of mature Picea abies in oldgrowth spruce forests. 
Description type:Original description 
Description:Description: Thallus indistinct, indeterminate, of hyphae and photobiont cells in the uppermost cell layer(s) of the substrate forming a white surface on which soralia are developed; hyphae colourless, 1.5–3 mm wide. Soralia irregular and effuse, discrete or a few becoming fused forming sorediate patches to a few mm in diameter, mottled pale brown due to a pigment in the outwardingly facing part of the external soredia, pale green where the external soredia have been shed and in particularly shaded niches such as bark crevices; soredia 10–20 μm, consoredia 15–30 μm in diameter. Medulla not evident. The uppermost layer of the substrate tends to get detached and fragmented forming small, white, flat, scales that often support soralia (Fig. 3). Photobiont unicellular, chlorococcoid, usually globose, 5–15 μm in diameter. Apothecia very rare (observed in a few specimens only), mostly poorly developed and misshaped, occasionally situated on the soralia, circular, 0.20–0.40 mm in diameter, without pruina; disc flat to deeply concave, pale brown or, rarely, dark brown, mat; margin usually raised above the disk, 0.04–0.08 mm wide, pale brown, mostly circular, rarely distinctly flexuose;. Excipulum 36–90 μm wide at upper rim, brown in outer part, colourless inside; hyphae branched; apical cell globose, to 3(–4) μm wide. Epihymenium brown; paraphyses usually unbranched, sometimes bifurcately branched in upper part, 1.5–2 μm wide; tips sometimes protruding unequally; uppermost cell widening to 3.5 μm, mostly with a brown cap; hymenium 36–55 μm tall, colourless; asci 8-spored, clavate to ± cylindrical, 20–34 × 10–14 μm, with a distinct K/I+ blue tholus, usually without an evident ocular chamber, sometimes with a short ocular chamber narrowing towards the ascus tip; spores simple, ellipsoid to oblong-ellipsoid, 7–10 × 2–4 μm. Hypothecium 48–96 μm tall, colourless, sometimes with oil drops. Pycnidia not observed. Chemistry: TLC: Lobaric acid. Colour reactions (soralia): C–, K–, KC+ fleetingly violet, Pd–. UV: Reaction of the soralia not evident against the white thallus/substrate surface. 
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