Arthonia vinosa (images of British lichens)

Thallus a thin, smooth or somewhat scurfy, greenish or yellowish cream crust, often mottled with brighter orange, with embedded, red-brown to brown-black, convex, irregularly shaped apothecia (typically about 0.5mm in diameter); ascospores 1-septate. Mostly on Oak (Quercus) or Alder (Alnus) in old woodland or parkland, widespread but local, largely absent from much of central and eastern England.

Refs: Smith et al. (2009), 170; Purvis et al. (1992), 87; Dobson (2005), 70 (photo); Dobson (2011), 76 (photo); Holien & Tønsberg (2008), 195 (photo); Wirth (1995), 1: 127, 135 (photo); Frahm et al. (2010), 72 (photo); Puntillo (1996), plate 4 (photo).

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Images of British Lichens