Varicellaria is a genus of crustose lichens. It is the only genus in the family Varicellariaceae. The genus contains 12 recognized species found worldwide. These lichens typically form pale bluish-grey or whitish-grey crusts on tree bark or rocks, and they produce a lichen product called lecanoric acid. Genetic studies have helped clarify the boundaries between species in this group, showing that where they grow (bark versus rock) and certain physical features are important for telling them apart.

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