Mycoblastus fucatus with Tremella lichenicola (images of British lichens)

Thallus thin, grey, smooth to minutely warted, commonly with a distinct black margin formed by the prothallus, yellowish green to blue-grey soredia formed in patches on the surface; apothecia rare, black, discoid. Widespread, on wood and smooth bark.

Refs: Spribille et al. (2011), Lichenologist 43: 458 (photos, with apothecia, as Violella fucata); Smith et al. (2009), 617; Purvis et al. (1992), 391 (as both M. fucatus and M. sterilis); Dobson (2005), 275 (photo); Dobson (2011), 283 (photo); Wirth (1995), 2: 600; van Herk & Aptroot (2004), 256-257 (photo).

Convincing molecular evidence (Spribille et al. (2011), Lichenologist 43: 455-466) shows that this species is wrongly placed in the genus Mycoblastus. It is now Violella fucata (Stirt.) T.Sprib.

Small, irregular, mostly convex, gelatinous lumps on the surface (as shown here) are the host-specific, parasitic fungus, Tremella lichenicola.

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Images of British Lichens