''Tephromela eviolacea'' is a species of corticolous,

crustose lichen Crustose lichens are lichens that form a crust which strongly adheres to the Substrate (biology), substrate (soil, rock, tree bark, etc.), making separation from the substrate impossible without destruction. The basic structure of crustose lichen ...

in the family

Tephromelataceae The Tephromelataceae are a family of lichenized fungi in the order Lecanorales. The family was circumscribed by Austrian lichenologist Josef Hafellner in 1984. Tephromelataceae comprises the genera '' Tephromela'', '' Calvitimela'', '' Mycoblastu ...

. Found the

Pacific Northwest The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though ...

of the United States at middle elevations, this lichen usually grows on bark of

maple ''Acer'' () is a genus of trees and shrubs commonly known as maples. The genus is placed in the family Sapindaceae.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 nd more or less continuously updated since http ...

trees, but has also has been reported from

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accep ...

Douglas fir The Douglas fir (''Pseudotsuga menziesii'') is an evergreen conifer species in the pine family, Pinaceae. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Oregon pine, and Columbian pine. There are three va ...

, and ''

Umbellularia californica ''Umbellularia californica'' is a large hardwood tree native to coastal forests and the Sierra foothills of California, and to coastal forests extending into Oregon. It is endemic to the California Floristic Province. It is the sole species in th ...

''. Typically lichen in the genus ''

Tephromela ''Tephromela'' is a genus of lichens in the family Tephromelataceae. There are about 25 species in this widespread genus. Species *'' Tephromela alectoronica'' *'' Tephromela antarctica'' *'' Tephromela arafurensis'' *''Tephromela atra ''T ...

'' have violet coloration of their

hymenium The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some ...

; ''T. eviolacea'' is distinguishable for being the only lichen in this region lacking this trait.

References

Lecanorales Lichens described in 2021 Lichens of North America Lichen species Taxa named by Bruce McCune {{Lecanorales-stub