About Teloschistes exilis (Mich.) Vain.
Teloschistes exilis (Mich.) Vain. is a corticolous (bark-dwelling), fruticose lichen that belongs to the family Teloschistaceae. It was first formally described in 1803 by French botanist André Michaux, under the name Physcia exilis. In 1890, Finnish lichenologist Edvard Vainio moved this taxon to the genus Teloschistes, giving it its current accepted scientific name. This lichen occurs across the Americas. Two secondary metabolites, also called lichen products, that have been isolated and identified from this species are parietin and teloschistin. In 1938, Vilmos Kőfaragó-Gyelnik described a form of this lichen named Teloschistes exilis f. inaequalis Gyeln. After studying the original type material of this form, which was collected from Argentina, researchers have proposed that this name is actually a synonym of Teloschistes nodulifer.