Punctelia jeckeri (images of British lichens)

Thallus foliose, grey-green when fresh, tinged brown and usually pruinose (lens needed) at the slightly upturned margins, grey when dry, underside pale brown, inner lobes developing marginal soralia, lobe surfaces with scattered, white dots (pseudocyphellae) that later also develop into soralia; apothecia apparently unknown. Evidently widespread and locally common on a variety of trees, but not distinguished from P. subrudecta until relatively recently.

Refs: Van Herk & Aproot (2000) Lichenologist 32: 233-246 (photos, detailed descriptions, as P. ulophylla); Smith et al. (2009), 770; Dobson (2005), 375-6 (photo, as P. ulophylla); Dobson (2011), 378 (photo); Whelan (2011), 135 (photo); van Haluwyn et al. (2009), 102-3 (photo); van Herk & Aptroot (2004), 326-7 (photo, as P. ulophylla, printed with green cast in my copy); Nordic Lichen Flora (2011) 4: 103, 165 (photo); Wirth (1995), 2: 667 (photo, as Parmelia subrudecta, but this species fide Van Herk & Aptroot); Wirth et al. (2004), 98 (photo, as Parmelia subrudecta but same photograph as previous reference); Frahm et al. (2010), 147 (photo).

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Images of British Lichens