Lichen

Symbiosis of fungi with algae

A lichen ( LY-kən, UK also LITCH-ən) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungus species, along with bacteria embedded in the cortex, or "skin", in a mutualistic relationship. Lichens are the lifeform that first brought the term symbiosis (as Symbiotismus) into biological context. Lichens have since been recognized as important actors in nutrient cycling and producers which many higher trophic feeders feed on, such as reindeer, gastropods, nematodes, mites, and springtails.

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