Lichen on a stone cross. Lichen growing on a stone cross and iron railings in a churchyard in unpolluted air. Lichens are formed from the a symbiotic

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Lichen on a stone cross. Lichen growing on a stone cross and iron railings in a churchyard in unpolluted air. Lichens are formed from the a symbiotic association between a fungus and an alga. The alga is contained within the hyphae (filaments) of the fungus. Lichens are slow-growing, and are usually found on stones and the bark of trees. They are sensitive to pollution, and are a good indicator of air quality. Photographed at Llanfaglan, North Wales, UK.

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Size: 3620px × 4827px
Photo credit: © CORDELIA MOLLOY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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