Verrucaria mucosa (images of British lichens)

Thallus forming discrete or extensive, green to dark olive or blackish patches on rocks, smooth and somewhat oily-glossy, sometimes with a white prothallus showing at the edges or in eroded cracks; perithecia minute, immersed in the thallus. Often very common on intertidal rocks, around the British coast where suitable habitat exists. Immersed perithecia can also be the parasitic Stigmidium marinum (Dobson, 2005).

Refs: Smith et al. (2009), 952; Purvis et al. (1992), 639; Orange (2008); Dobson (2005), 451 (photo); Dobson (2011), 457, 458 (photo); Whelan (2011), 150 (photo); Thomson (1997), 640.

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Images of British Lichens