Verrucula Clauzadaria

''Verrucula'' is a genus of lichenicolous (lichen-dwelling) lichen. 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.

Description

''Verrucula'' lichens have a thallus that is areolate to a mixture of squamulose and areolate, and is sometimes reduced in form. The upper cortex is only weakly developed, and is termed a pseudocortex. The excipulum (the ring-shaped layer surrounding the hymenium) is pale except for the pale to pale brown area around the ostiole. Ascospores are colorless, and usually simple, although in rare instances they have a single septum. Pycnidia in ''Verrucula'' are similar in form to those found in genus ''Dermatocarpon''. This is pycnidial type is characterised by its paraplectenchymatous net (paraplectenchyma is a fungal tissue with a cellular structure superficially like the parenchyma of vascular plants) and its multiple cavities.

Species

, Species Fungorum accepts 16 species of ''Verrucula''. The following list gives the species name, author citation (using standard abbreviations), year of publication, and host lichen. The host specificity in genus ''Verrucula'' is quite high, as each species seems to parasitise a single host.
* ''Verrucula arnoldaria'' – ''Calogaya arnoldii''
* '' Verrucula biatorinaria'' – ''Calogaya biatorina''
* '' Verrucula clauzadaria'' – ''Caloplaca clauzadeana''
* ''Verrucula coccinearia'' – ''Caloplaca coccinea''
* ''Verrucula coronataria'' – ''Flavoplaca coronata''
* '' Verrucula elegantaria'' – ''Xanthoria elegans''
* '' Verrucula helvetica'' – ''Leproplaca cirrochroa''
* ''Verrucula hladuniana'' – ''Flavoplaca marina''
* ''Verrucula inconnexaria'' – ''Caloplaca inconnexa''
* ''Verrucula lactearia'' – ''Xanthocarpia lactea''
* ''Verrucula maritimaria'' – ''Flavoplaca maritima''
* '' Verrucula microspora'' – ''Variospora velana''
* ''Verrucula navasianaria'' – ''Flavoplaca navasiana''
* ''Verrucula polycarparia'' – ''Flavoplaca polycarpa''
* '' Verrucula protearia'' – ''Leproplaca proteus''
* ''Verrucula pusillaria'' – ''Calogaya pusilla''

Some species previously classified in ''Verrucula'' have since been reduced to synonymy with other species, or have been transferred to different genera:

*''Verrucula ahlesiana'' (= ''Laestadia ahlesiana'')
*''Verrucula cahirensis'' (= '' Guignardia cahirensis'')
*''Verrucula egyptiaca'' (= ''Guignardia egyptiaca'')
*''Verrucula fraudulosa'' (= ''Verruculopsis lecideoides'')
*''Verrucula fuscella'' (= '' Verrucaria fuscella'')
*''Verrucula granulosaria'' (= ''Verrucaria latericola'')
*''Verrucula latericola'' (= ''Verrucaria latericola'')
*''Verrucula lecideoides'' (= ''Verruculopsis lecideoides'')
*''Verrucula rheitrophila'' (= ''Hydropunctaria rheitrophila'')

References

{{Taxonbar, from=Q10714475

Verrucariales
Eurotiomycetes genera
Taxa described in 1896
Lichenicolous fungi