Xenonectriella subimperspicua
Xenonectriella subimperspicua is a species of lichenicolous fungus in the family Nectriaceae. It has been recorded from South America, Europe, and New Zealand. Taxonomy. The fungus was first formally described by Carlo Luigi Spegazzini in 1898 as a member of genus "Nectria". Spegazzini collected the type specimen from South America, where it was growing on "Punctelia constantimontium". In 1984, Rolf Santesson proposed to transfer the taxon to genus "Nectriella". Rosalind Lowen transferred it and several other lichenicolous species to "Pronectria" in 1990. Finally, Javier Etayo transferred the species to the genus "Xenonectriella" in 2017, giving it the binomial  name by which it is currently known. Hosts. One of its hosts is the common foliose lichen species "Punctelia borreri". Infection by "X. subimperspicua" creates discoloured or bleached areas on the thallus of the host; the perithecia of the fungus then become more readily visible. Two varieties of "Xenonectriella subimperspicua" have been defined: var. "subimperspicua" mostly parasitizes "Parmelia" and "Punctelia" but has also been recorded on "Physcia", while var. "degenerans" parasitizes "Parmotrema".