Hypotrachyna taylorensis (images of British lichens)

Thallus foliose, light grey, lobes rounded or rather square at the tips and with side-lobes curved around to enclose the sinuses, edges turned down and tinged tan-brown, surface initially smooth but in older lobes becoming obscurely reticulate and readily abrading, with production of numerous lobules, undersurface black, dark brown at margins, with repeatedly branched rhizines, soralia absent; apothecia rare. Lobes overlap and have been described by Dobson (2005, 2011) as "like ripples of waves on a sandy beach". Very local in high rainfall areas of western Britain, on mossy trunks and rocks, generally in ancient woodland.

Refs: Smith et al. (2009), 442; Purvis et al. (1992), 431 (as Parmelia); Dobson (2005), 195 (photo); Dobson (2011), 200 (photo); Jahns (1983), 196-7 (photo, as Parmelia); Lichen Atlas of the British Isles 1: 1023 (1995) (as Parmelia).

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Images of British Lichens