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Leptogium azureum (Sw.) Mont.
Family: Collemataceae
[Collema azureum (Sw.) Ach.,  more]
Leptogium azureum image
Stephen Sharnoff  
Thallus: foliose, 2-9 cm in diam., adnate, subdichotomously to irregularly lobate lobes: irregular, elongate, +plane, separate, 1-5 mm wide, (50-)80-100(-150) µm thick; apices: rotund, entire to lobulate, occasionally upturned upper surface: bluish gray to medium gray, usually dull, smooth to somewhat roughened but not wrinkled, not isidiate internal anatomy: with upper and lower cortices consisting of a single layer of irregularly isodiametrical cells 5-9 µm in diam., internally with loosely interwoven chains of Nostoc and hyphae lower surface: pale to medium gray, wrinkled, with scattered tufts of white hairs Apothecia: common, laminal, sessile to short stipitate, 0.2-2.5 mm wide disc: light brown to red-brown, concave to plane margin: thalline, concolorous with the thallus or cream-colored, entire or occastionally with microphylline outgrowths exciple: euparaplectenchymatous, often poorly developed centrally but up to 35 µm thick marginally hymenium: hyaline below and thinly brown above, 90-150 µm tall; paraphyses: unbranched, 1-2 µm wide, slightly inflated apically; subhymenium: yellow to pale brown, 35-70 µm thick asci: cylindrico-clavate, 8-spored ascospores: hyaline, submuriform, 3-5-septate transversely, 0-1-septate longitudinally, ellipsoid to subfusiform, 14-26 x 6-9 µm Pycnidia: not observed Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on bark and sometimes acidic rocks World distribution: widespread, pantropical, extending into some temperate regions in North and South America, Australasia, Asia and Africa Sonoran distribution: Baja California Sur and Sinaloa. Notes: Leptogium azureum is a characteristically blue-gray, large-lobed species, which, when lobulate, may be confused with L. cyanescens, a thinner, more gray species with at least with some coralloid isidia, though sometimes also some lobules occur.
Leptogium azureum image
Troy McMullin  
Leptogium azureum image
Troy McMullin  
Leptogium azureum image
Gary Perlmutter  
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image
Leptogium azureum image