Verrucula

Verrucula is a genus of lichenicolous (lichen-dwelling) lichens in the family Verrucariaceae. Species in the genus are parasitic on saxicolous (rock-dwelling), crustose lichens, including Xanthoria elegans as well as lichens from genus Caloplaca that contain chemical substances called anthraquinones.

==Taxonomy== Verrucula was originally circumscribed in 1896 by Austrian lichenologist Julius Steiner to contain a group of parasitic Verrucaria species. It was subsequently little used until 2007, when it was resurrected for use for Verrucaria found as parasites on Caloplaca with anthraquinone compounds. Other parasitic species were moved to genus Verruculopsis; these two genera are morphologically quite similar. Molecular phylogenetic analysis shows that Verrucula has a sister taxon relationship with Placocarpus in the family Verrucariaceae.