Hypotrachyna endochlora (images of British lichens)

Thallus foliose, lobes smooth, light blue-grey to grey or tinged yellowish, generally rather square at the tips, edges flat, surface brittle, flaking to expose the diagnostic pale yellow to greenish medulla, central parts of thallus often with numerous lobules, undersurface black, with repeatedly branched rhizines, soralia rather large, terminal and well delimited, grey to dark grey, with coarse soredia; apothecia rare. Local in damp woodland in high rainfall areas of western Britain.

Refs: Smith et al. (2009), 440; Purvis et al. (1992), 431 (as Parmelia); Lichen Atlas of the British Isles 1: 994 (1995) (as Parmelia).

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Images of British Lichens