Umbilicaria torrefacta (images of British lichens)

Thallus attached at central point, grey-brown to dark brown above, lacking isidia, often much distorted or crumpled, margins ragged and perforated, lower surface brown to black, with pale, radiating, irregular, rope-like lamellae, thalloconidia absent; apothecia black, multiply-infolded (gyrose). Locally common on exposed rocks and boulders in the north and west. The lamellae on the underside distinguish this species from the otherwise similar U. hyperborea.

Refs: Krzewicka (2004), 68; Smith et al. (2009), 917; Purvis et al. (1992), 620; Dobson (2005), 437-8 (photo); Dobson (2011), 445 (photo); Jahns (1983), 226-227 (photo); Wirth (1995), 2: 930, 939 (photo); Moberg & Holmåson (1984), 158 (photo); Hansen & Anderson (1995), 70 (photo); Puntillo (1996), plate 41 (photo); Hinds & Hinds (2007), 486 (photo); Brodo et al. (2001), 708 (photo); Pope (2005), 42 (photo); McCune & Geiser (2009), 352 (photo).

lastdragon.org

Images of British Lichens