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Caloplaca fraudans (Th. Fr.) H. Olivier
Family: Teloschistaceae
[Blastenia fraudans (Th. Fr.) B. de Lesd.]
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Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus thin, forming yellowish pale patches on the rock or invisible. Apothecia to 1 mm broad, sessile with constricted base; margin lighter than disk, thin, rusty-reddish to deep orange; disk flat, dull, rust-red to darkened rusty red; hypothecium hyaline, oil-inspersed, 1+ blue; epihymenium reddish brown, granular, K+ violet; hymenium 85-90 µm, hyaline below, upper part reddish, 1+ blue; paraphyses coherent, tips not thickened; spores 8, polarilocular, ellipsoid, 10-17 x 5-6 µm, septum 2-3.5 µm.

This species grows on rocks and old bones, occasionally on old wood. It is circumpolar arctic.

C. arenaria differs from this in having smaller apothecia, 0.2-0.5 mm, concolorous disk and margins, and usually a narrow septum, 1.5-3 µm. Very similar to this also is C. leptocheila Magnusson, which has smaller apothecia, less than 0.5 mm, the margin and disk concolorous orange to rust-red instead of the margin lighter than the disk as in C. fraudans, and a similar 1+ blue excipular cortex, the spores being 13-15 X 4.5-6.5 µm, the septum 2.5-5.5 µm. C. leptocheila grows on noncalcareous rocks in Europe and Asia and was recently reported from Disko Island, Greenland, by Hansen, Poelt, & S0chting (1987). Also very similar is C. lithophila Magnusson, which has orange apothecia with I— excipular cortex, the spores 10-14 X 5-6.5 µm and septum 3-3.5 µm. This was reported from bird cliffs on Disko Island, Greenland, by Hansen, Poelt, & Sochting as var. elaeophora Hansen, Poelt, & S0chting with oil droplets in the upper paraphyses cells.

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Caloplaca fraudans image
Caloplaca fraudans image
Caloplaca fraudans image
Jason Dart  
Caloplaca fraudans image
Caloplaca fraudans image
Caloplaca fraudans image
Caloplaca fraudans image
Jason Dart  
Caloplaca fraudans image
Caloplaca fraudans image
Caloplaca fraudans image
Caloplaca fraudans image
Jason Dart