Ochrolechia tartarea (images of British lichens)

Thallus crustose, coarsely warted, cream, pale grey or tinged with buff, soredia absent; apothecia usually abundant, with thick, notched, flexuous margins and pale pink- to yellow-brown disks. Can be very similar to O. androgyna, with which it grows, but lacks soredia; it differs from variants of O. parella with non-pruinose disks in being more coarsely granular, and can be confirmed by its thallus context testing red with sodium hypochlorite. Mainly in upland areas and in the north and west, on base-poor rocks and nutrient-poor tree bark.

Refs: Smith et al. (2009), 630; Purvis et al. (1992), 400; Dobson (2005), 285-286 (photo); Dobson (2011), 290 (photo); Britton (2008) 38 (photo); Dalby & Dalby (2005), 15 (photo); Jahns (1983), 254-255 (photo); Wirth (1995), 2: 612; Moberg & Holmåson (1984), 207 (photo); Holien & Tønsberg (2008), 177 (photo); Puntillo (1996), plate 26 (photo); Thomson (1997), 435.

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Images of British Lichens