Lichen species growing on an Opuntia cactus leaf. Two forms of lichen are seen here: a grey foliose (flat with leaf-like lobes) species; and an orange

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Lichen species growing on an Opuntia cactus leaf. Two forms of lichen are seen here: a grey foliose (flat with leaf-like lobes) species; and an orange fruticose (branched) species. Lichens consist of a fungus and an algae living together in symbiotic association. Lichens play an important role in colonising bare mountain and arctic regions where few other plants can exist. Here, they are growing in an arid area on the South American Andes where the cactus Opuntia also survives. Photographed north of Quito, Ecuador.

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Size: 3558px × 4976px
Photo credit: © DR MORLEY READ/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: botany, cactus, foliose, fruticose, leaf, lichen, lichens, mutualism, nature, opuntia, plant, sp., symbiosis, symbiotic, type