Rock tripe (Umbilicaria pustulata or Lasallia pustulata) is an umbilicate lichen with the upper thallus surface with convex pustules; its color varies

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Rock tripe (Umbilicaria pustulata or Lasallia pustulata) is an umbilicate lichen with the upper thallus surface with convex pustules; its color varies between gray and brown or yellow. This photo was taken in Sierra de Gredos, Avila, Spain.

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Size: 4256px × 2832px
Photo credit: © José María Barres Manuel / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: alga, avila, castilla, close, de, fungus, gredos, lasallia, leon, lichen, pustulata, pustule, rock, sierra, spain, symbiosis, thallus, tripe, umbilicaria, umbilicate