Rock pimples

Staurothele
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Eurotiomycetes
Subclass:	Chaetothyriomycetidae
Order:	Verrucariales
Family:	Verrucariaceae
Genus:	Staurothele Norman
Type species
Staurothele clopima (Wahlenb.) Th. Fr.
Species
Staurothele arctica Staurothele areolata Staurothele bacilligera Staurothele caesia Staurothele clopima Staurothele fissa Staurothele frustulenta Staurothele geoica Staurothele guestphalica Staurothele hymenogonia Staurothele pallidipora Staurothele rufa Staurothele rugulosa Staurothele rupifraga Staurothele succedens

Staurothele is a genus of fungi in the family Verrucariaceae. When the fungus is part of a lichen, the genus of lichen is commonly called rock pimples.

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Wikipedia