# Abrothallus

Abrothallus is a genus of lichenicolous (lichen-dwelling) fungi. It is the only genus in the monotypic family Abrothallaceae, which itself is the sole taxon in the order Abrothallales.

## Taxonomy

The genus was circumscribed by the Italian botanist Giuseppe De Notaris in 1849. The classification of the genus in either family or order was uncertain until molecular phylogenetic analysis revealed the group as an independent lineage in the class Dothideomycetes. Both the family and the order were circumscribed in 2013 by Sergio Pérez-Ortega and Ave Suija.
In 2012 Mikhail Zhurbenko proposed the genus Epinephroma to contain E. kamchatica; later analysis showed it to be the anamorph of an Abrothallus species, and now Epinephroma is placed in synonymy with Abrothallus. Other synonyms are Abrothallomyces, Phymatopsis, and Pseudo-lecidea.

## Description

There are several morphological characteristics help define the genus Abrothallus. These include: spherical (or nearly so) ascomata without a margin or well-defined edge that are sometimes dusted with golden or green pruina; bitunicate asci (i.e., with two functional ascal wall layers) that have four to eight ascospores; brown, 2- to 4-celled, warted asymmetric ascospores; paraphyses that are ramified-anastomosed; and the presence of an epihymenium (the uppermost layer of the hymenium) with granulose pigments that often dissolve in potassium hydroxide.

## Species

As of October 2024, Species Fungorum (in the Catalogue of Life) accepts 44 species of Abrothallus:
* Abrothallus acetabuli Diederich (1990) – parasitic on Parmelia acetabulum; from Europe
* Abrothallus altoandinus Flakus, Etayo & Rodr.Flakus (2023)
* Abrothallus boomii Pérez-Ort. & Suija (2015)
* Abrothallus brattii (S.Y.Kondr.) Suija & Pérez-Ort. (2015)
* Abrothallus bryoriarum Hafellner (1994)
* Abrothallus caerulescens I.Kotte (1909)
* Abrothallus canariensis Pérez-Ort., van den Boom & Suija (2015)
* Abrothallus cetrariae I.Kotte (1909)
* Abrothallus cladoniae R.Sant. & D.Hawksw. (1990)
* Abrothallus curreyi Linds. (1867) – New Zealand
* Abrothallus doliiformis Pérez-Ort. & Suija (2015)
* Abrothallus eriodermae Suija, Etayo & Pérez-Ort. (2015)
* Abrothallus ertzii Suija & Pérez-Ort. (2015)
* Abrothallus etayoi Pérez-Ort. & Suija (2015)
* Abrothallus granulatae Wedin (1994) – parasitic on Pseudocyphellaria granulata; from Argentina
* Abrothallus halei Pérez-Ort., Suija, D.Hawksw. & R.Sant. (2010) – parasitic on Lobaria quercizans and L. pulmonaria; from Europe and North America
* Abrothallus heterodermiicola Etayo & F.Berger (2017)
* Abrothallus hypotrachynae Etayo & Diederich (2002)
* Abrothallus kamchatica (Zhurb. & Stepanch.) Pérez-Ort. & Suija (2015)
* Abrothallus lobariae (Diederich & Etayo) Diederich & Ertz (2018)
* Abrothallus macrosporus Etayo & R.Sant. (2010) – South America
* Abrothallus microspermus Tul. (1852)
* Abrothallus nephromatis Suija & Pérez-Ort. (2015)
* Abrothallus niger Etayo (2017) – Ecuador
* Abrothallus parmeliarum (Sommerf.) Arnold (1874)
* Abrothallus parmotrematis Diederich (2011)
* Abrothallus peyritschii (Stein) I.Kotte (1909)
* Abrothallus pezizicola Diederich & R.C.Harris (2003)
* Abrothallus prodiens (Harm.) Diederich (1989)
* Abrothallus prodiens (Harm.) Clauzade, Diederich & Cl.Roux (1989)
* Abrothallus psoromatis (Zhurb. & U.Braun) Diederich & Zhurb. (2018)
* Abrothallus puntilloi Brackel (2016)
* Abrothallus ramalinae Diederich (2017) – Seychelles
* Abrothallus santessonii (D.Hawksw.) A.Suija, D.Hawksw. & Pérez-Ort. (2018)
* Abrothallus secedens Wedin & R.Sant. (1994) – commensalistic on species of Pseudocyphellaria; from Argentina and Kenya
* Abrothallus stereocaulorum Etayo & Diederich (2002)
* Abrothallus stictarum Etayo (2002) – Colombia
* Abrothallus stroblii Hafellner (2008)
* Abrothallus subhalei Etayo, Flakus & Kukwa (2019)
* Abrothallus suecicus (Kirschst.) Nordin (1964)
* Abrothallus teloschistis Brackel, Pérez-Ortega & Suija (2015)
* Abrothallus tetrasporus (Etayo & Osorio) Etayo, Flakus & Rodr.Flakus (2023)
* Abrothallus tulasnei M.S.Cole & D.Hawksw. (2001) – parasitic on Xanthoparmelia somloensis; from Canada
* Abrothallus usneae Rabenh. (1861)
* Abrothallus welwitschii Mont. (1856)