Parmelia sulcata (images of British lichens)

Thallus foliose, blue-grey (becoming bronze when old and semi-moribund), with conspicuous, white pseudocyphellae forming networks on the lobe surfaces. On older thalli, the pseudocyphellae develop into irregular, laminar soralia. Widespread and common on branches and trunks of trees and less often on rocks.

Refs: Smith et al. (2009), 653; Purvis et al. (1992), 425; Dobson (2005), 302-303 (photo); Dobson (2011), 305 (photo); Jahns (1983), 198-9 (photo); Whelan (2011), 121 (photo); van Haluwyn et al. (2009), 98-9 (photo); van Herk & Aptroot (2004), 276-277 (photo); Hansen & Anderson (1995), 46 (photo); Wirth (1995), 2: 646, 663 (photo); Wirth et al. (2004), 97 (photo); Frahm et al. (2010), 122 (photo); Moberg & Holmåson (1984), 94 (photo); Holien & Tønsberg (2008), 57 (photo); Nordic Lichen Flora (2011) 4: 89, 163 (photo); Pope (2005), 34 (photo); Brodo et al. (2001), 483 (photo); Hinds & Hinds (2007), 340 (photo); McCune & Geiser (2009), 225 (photo); Lichen Atlas of the British Isles 1: 1022 (1995).

P. encryptata is a newly described "species" distinguished from P. sulcata by molecular data, arbitrarily calculated genetic distance and a strictly cladistical species concept - see Molina et al. (2011) Lichenologist 43: 585-601. Although separable by gel electrophoresis, it is not yet known to have any morphological or ecological validity and its clade is incorporated without difficulty within a broader concept of P. sulcata. It is impossible to know whether any of the photographs below represent this taxon, which I consider a synonym of P. sulcata, deserving, at most, infraspecific status as a chemical variant.

Lichenicolous fungi on P. sulcata include Marchandiomyces corallinus and Nesolechia oxyspora.

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Images of British Lichens