Normandina pulchella (images of British lichens)

Thallus of blue-grey, disk-like squamules, approx. 2mm in diameter, each with a distinct, raised rim and often with blue-grey to greenish soredia on the margins and surface; fruit-bodies evidently occasional, as perithecia immersed in the squamules (formerly but incorrectly claimed as a separate, parasitic fungus). Widespread but especially in the north and west, generally on old mosses or other lichens on trunks and rocks.

Refs: Smith et al. (2009), 626; Purvis et al. (1992), 397 (but perithecia misinterpreted); Dobson (2005), 282 (photo); Dobson (2011), 202 (photo, poorly printed); Whelan (2011), 117 (photo); van Haluwyn et al. (2009), 220-1 (photos); van Herk & Aptroot (2004), 260-261 (photo); Jahns (1983), 260-1 (photo); Wirth (1995), 2: 609 (photo); Wirth et al. (2004), 310 (photo); Frahm et al. (2010), 96 (photo), 97; Moberg & Holmåson (1984), 219 (photo); Holien & Tønsberg (2008), 132 (photo); Arup et al. (1997), 192 (photo); Thor & Arvidsson (1999), 290 (photo), 374; Puntillo (1996), plate 25 (photo); Brodo et al. (2001), 461-2 (photo); Hinds & Hinds (2007), 331 (photo).

In moorland it could be confused with the squamules of Lichenomphalia hudsoniana.

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Images of British Lichens