Alectoria

lichen

Also known as: Alectoride

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Last updated

June 18, 2026

Quick Summary

Alectoria is a genus of lichens belonging to the Usneaceae family. These lichens are characterized by a dark brown, erect or pendulous, and much-branched thallus that is cylindrical in form.1

Lichens, in general, are a symbiotic association between one or more fungus species and an alga or cyanobacterium. The fungus (mycobiont) provides structure and protection, while the alga or cyanobacterium (phycobiont) performs photosynthesis, providing nutrients for both partners. Lichens can grow in diverse environments, from harsh, bleak regions to more temperate areas, and exhibit various forms such as crustose, foliose, and fruticose.2

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fungus
Form and function of lichens
Alectoria and Cladonia have haustoria that do not penetrate far beyond the algal cell wall. A few phycobionts, such as Coccomyxa and Stichococcus, which are not penetrated by haustoria, have thin-walled cells that are pressed close to fungal hyphae.
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Alectoria and Cladonia have haustoria that do not penetrate far beyond the algal cell wall. A few phycobionts, such as Coccomyxa and Stichococcus, which are not penetrated by haustoria, have thin-walled cells that are pressed close to fungal hyphae.
Read More