Lepraria incana (images of British lichens)

Thallus a diffuse, thin, powdery crust, lacking a medulla or any marginal differentiation into lobes, pale grey to distinctly blue-grey, apothecia unknown. In shaded places on acid rocks, walls and tree-trunks, widespread and evidently common, but part of a complex of species that require thin-layer chromatography for certain identification. (Photograph shown here is named on morphological grounds.)

Refs: Smith et al. (2009), 538; Purvis et al. (1992), 346; Dobson (2005), 242 (photo); Dobson (2011), 248-9 (photo); Whelan (2011), 107 (photo); Wirth (1995), 2: 538 (photo), 541 (photo); van Herk & Aptroot (2004), 232-233 (photo); Lichen Atlas of the British Isles 4: 1974 (1999).

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Images of British Lichens