Lepraria vouauxii (images of British lichens)

Thallus a pale to greyish-green, diffuse, rather thick, granular crust, margins variably delimited and sometimes minutely lobate, granules often eroding to expose a white medulla; apothecia unknown. On nutrient-rich bark and stonework in shaded and sheltered situations, widespread but more common in the south and east. The photographed material is on a wall somewhat sheltered from direct rain but where water seeps down. The thallus lobes are generally indistinct but well developed adjacent to the rain channels.

Refs: Smith et al. (2009), 540; Purvis et al. (1992), 349 (as Leproloma); Dobson (2005), 245 (photo, as Leproloma); Dobson (2011), 250-1 (photo); Wirth (1995), 2: 546 (photo, as Leproloma); Hansen & Anderson (1995), 102 (photo, as Leproloma); van Herk & Aptroot (2004), 236-237 (photo, as Leproloma); Lichen Atlas of the British Isles 4: 1604 (1999).

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Images of British Lichens