Lecidea

Genus of lichenised fungi in the family Lecideaceae

Lecidea is a genus of crustose lichens with a carbon-black ring or outer margin (exciple) around the fruiting body disc (apothecium), usually found growing on (saxicolous) or in (endolithic) rock. Lichens that have such a black exciple are called lecideine, meaning "like Lecidea, even if they are not in this genus. Members of the genus are commonly called disk lichens or tile lichens.

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