Melanelixia fuliginosa ssp. fuliginosa (images of British lichens)

Thallus dark to blackish brown, shining, older parts becoming clothed with dense, velvety, cylindrical to branched-coralloid isidia, which leave white scars when rubbed off. Generally on siliceous rocks, widespread and locally common. (M. fuliginosa subsp. glabratula green to warm brown, less densely isidiate, mostly on trees, better treated as a separate species.)

Refs: Smith et al. (2009), 571; Purvis et al. (1992), 434 (as Parmelia glabratula subsp. fuliginosa); Dobson (2005), 263 (photo, as Melanelia); Dobson (2011), 267 (photo); Wirth (1995), 2: 642 (as P. glabratula var. fuliginosa); Moberg & Holmåson (1984), 90 (photo, as P. glabratula var. fuliginosa); Nordic Lichen Flora (2011) 4: 73, 159 (photo, as species, printed too dark).

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Images of British Lichens