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 Add this item to the list  803598 Original description
   
Remarks (public):This species is characterised chiefly by the combination of the thallus containing atranorin only, and by the conspicuously inspersed hymenium. In other respects, such as disposition of pigments and the yellow-brown hypothecium, it is very similar to L. elaeochroma. Additional, more subtle characters that distinguish L. destituta from L. elaeochroma include the apothecia, which generally do not become markedly convex with an excluded exciple, and the lack of brownish epihymenial granules; the ecology of the two taxa (see below) is also starkly different. Although ascospores of L. destituta falls within the size range of L. elaeochroma, they are nevertheless slightly longer and broader (as demonstrated by mean values). It is probably due to the lack of epihymenial granules that the blue-green apothecial pigment in L. destituta often appears relatively bright. The characteristic inspersion of the hymenium is most pronounced in New South Wales and South Australian specimens, whereas in Tasmanian material, this is mostly restricted to the base of the hymenium. The crystals and droplets do not fluoresce in polarised light, nor dissolve in KOH or HNO3, but they yield a curious pinkish reaction in the former reagent. In the field, L. destituta is most likely to be confused with species of the Buellia disciformis (Fr.) Mudd group. 
Description type:Original description 
Description:Thallus typically areolate, deeply cracked, rather lumpy and uneven, more rarely very thin, effuse and revealing a blue-black prothallus beneath, pale pinkish brown, grey-brown to whitish grey, undelimited, esorediate, forming irregular patches c. 1–5 cm wide. Apothecia 0.2–0.9 mm wide, sessile, basally constricted; disc mostly persistently plane, sometimes becoming undulate but only rarely convex, black, matt, epruinose. Proper excipulum black, matt to glossy, persistent, entire, in section 20–40 µm thick, ± opaque brown within, unchanged in K, N+ intensifying orange-brown, also with additional blue-green, N+ crimson pigment, especially at the upper and outer edges. Hypothecium 40–90 µm thick, pale yellow-brown to yellow-orange, intensifying yellow-orange in K and N. Hymenium 60–90 µm thick, separating easily in K, not overlain by epihymenial granules but densely inspersed, especially towards the base, with minute, colourless crystals and oil droplets that do not dissolve in K, in the upper part intensely greenish blue, K ± grey-green, N+ crimson, towards the base mostly colourless, often K± very faint pinkish. Asci 45–60  14–22 µm. Paraphyses 1.5–2.5 µm thick, simple; apices usually expanded to 2–4.5 µm thick, mostly with an external blue-green, N+ crimson cap but sometimes unpigmented. Ascospores broadly ellipsoid, occasionally slightly bent, 11–13.7–16(–17)  (5.5–)6–7.2–9 µm. Conidiomata not observed.

Chemical composition: atranorin , ±and chloroatranorin
 
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