Melanelixia fuliginosa subsp. glabratula (images of British lichens)

Thallus green to warm brown (not always dark brown as in Dobson (2005) key, corrected 2011), shining, older parts with few to abundant cylindrical or branched-coralloid isidia reaching 0.8mm or more in height, leaving white scars when rubbed off. On deciduous tree bark and fences, rarely rocks, generally common throughout Britain.

Refs: Smith et al. (2009), 572; Purvis et al. (1992), 433 (as Parmelia glabratula subsp. glabratula); Dobson (2005), 262 (as Melanelia); Dobson (2011), 268 (photo); van Haluwyn et al. (2009), 62-3 (photo, as M. fuliginosa); Wirth (1995), 2: 642, 644, 653 (photo, bright green variant, as P. glabratula); Wirth et al. (2004), 106 (photo, as P. glabratula); Frahm et al. (2010), 115 (photo); van Herk & Aptroot (2004), 244-245 (photo, as Melanelia); Holien & Tønsberg (2008), 54 (photo, as Melanelia); Nordic Lichen Flora (2011) 4: 74, 159 (photo, as M. glabratula, printed too dark); Hinds & Hinds (2007), 310-311 (photo, as Melanelia).

Better treated as a separate species. Closely similar are other Melanelixia taxa and Melanohalea spp., notably: M. fuliginosa subsp. fuliginosa, blackish brown, densely isidiate and looking like velvet, mostly on rocks; Melanelixia subaurifera, commonly with M. fuliginosa subsp. glabratula on smaller twigs, rather less shining surface and very short (about 0.2mm), more globose isidia, which leave white or pale yellow scars when rubbed off.

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Images of British Lichens