Candelariella vitellina (images of British lichens)

Thallus of dispersed to densely aggregated, minute, ± flat, yellow to yellow-orange granules, non-reactive with KOH; apothecia bright yellow, asci with 12-32 ascospores. Widespread and very common on rocks and walls.

Refs: Smith et al. (2009), 278; Purvis et al. (1992), 161; Dobson (2005), 112-113 (photo); Dobson (2011), 122 (photo); Allen (2007), 18 (photo); van Haluwyn et al. (2009), 144-5 (photo); van Herk & Aptroot (2004), 112-113 (photo); Wirth (1995), 1: 244, 247 (photo); Wirth et al. (2004), 221 (photo); Frahm et al. (2010), 62 (photo); Puntillo (1996), plate 10 (photo); Brodo et al. (2001), 208-9 (photo); Thomson (1997), 188-9 (photo); Walewski (2007), 60 (photo).

States with a dispersed thallus are liable to be confused with C. aurella, but the latter has 8-spored asci. Species of the Caloplaca citrina group may also look similar but react purple with potassium hydroxide (KOH).

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Images of British Lichens