Fungalpedia – Note 2648, Verrucula
Verrucula J. Steiner.
Citation when using this data: Meng QF et al. – Fungalpedia.
Index Fungorum, Faceoffungi, MycoBank, GenBank, Fig 1.
Classification: Verrucariaceae, Verrucariales, Chaetothyriomycetidae, Eurotiomycetes, Pezizomycotina, Ascomycota, Fungi.
Verrucula was established by Steiner (1896) with a brief diagnosis to accommodate two species: V. egyptiaca and V. cahirensis. In the monograph by Navarro-Rosinés et al. (2007), V. aegyptiaca was designated as the lectotype. Although V. aegyptiaca was synonymized with Guignardia egyptiaca in Index Fungorum (2025), the two species have different basionyms: Guignardia egyptiaca was transferred from Laestadia aegyptiaca (Reichert 1921), while Verrucula aegyptiaca came from Verrucaria aegyptiaca (Steiner 1896). As a result, Verrucula aegyptiaca remains valid within Verrucula.
This genus is characterized by whitish, grayish, or brown areolate to squamulose thalli parasitic on Caloplaca and Xanthoria elegans. The perithecioid ascomata are globose, deeply immersed, and black in the upper part. Asci are eight-spored, clavate, and slightly thickened at the top. Ascospores are colorless, mostly simple, occasionally uniseptate, and vary from globose to fusiform. Pycnidia are globose or pyriform, resembling smaller ascomata, and have ampulliform conidiogenous cells. Conidia are simple, straight or slightly curved and bacilliform (Navarro-Rosinés et al. 2007).
There are 34 records in Index Fungorum (2025), however, only 22 were included in the monograph of Navarro-Rosinés et al. (2007), excluding Verrucula glaucina and V. monstrosa. Verrucula glaucina was introduced by Steiner (1897) and is listed in Index Fungorum (2025) and MycoBank (2025). Verrucula monstrosa was included in Index Fungorum (2025), but later transferred to Verrucaria monstrosa by Jatta (1900), according to the MycoBank.
Verrucula subcrustosa was transferred from Endocarpon cinerascens var. subcrustosum Nyl. by Steiner (1898) and later transferred to Dermatocarpon subcrustosum by Zahlbruckner in (1921). Despite its listing under Verrucula in Index Fungorum (2025) and its synonymization with Endocarpon in MycoBank, it should be classified under Dermatocarpon, following the synonym date. Verrucula tarraconensis was described by Navarro-Rosinés et al. Roux (2007) and accepted by Diederich et al. (2018a), however, it is listed as invalid in MycoBank (2025) and Index Fungorum (2025). Thus, we included this species in our checklist.
Verrucula ahlesiana was originally described as Sagedia ahlesiana Hepp, then transferred to Verrucula by Steiner (1898), subsequently to Laestadia by Vouaux (1912), and later to Guignardia by Keissler (1930). However, Guignardia ahlesiana is nomenclaturally invalid under Art. 36.1(a) of the Shenzhen Code (Turland et al. 2018). Current taxonomic consensus (Index Fungorum & MycoBank, 2025) maintains Laestadia ahlesiana (Vouaux) as the correct name.
Verrucula granulosaria was transferred from Verrucaria granulosaria Clauzade & Zehetl. by Navarro-Rosinés et al. (2001), but later included under Verrucaria latericola in Species Fungorum (2024) and Index Fungorum (2025), contrary to MycoBank (2025). Here, we accept its placement within Verrucula.
In conclusion, Verrucula comprises 21 lichenicolous species. Phylogenetic analysis based on LSU and RPB1 conducted by Gueidan et al. (2009) showed that Verrucula is closely related to the Placocarpus within Verrucariaceae.
Type species: Verrucula egyptiaca (Müll. Arg.) J. Steiner.
= Verrucaria egyptiaca Müll. Arg.
Other accepted species: Species Fungorum – search Verrucula
Figure 1 – Verrucula egyptiaca spores redrawn from Navarro-Rosinés et al. (2007)
References
Jatta A 1900 – Sylloge Lichenum Italicorum. 1–623.
Keissler KV 1930 – Rabenhorst’s Kryptogamen-Flora, Pilze – Die Flechtenparasiten. 8, 1–712.
Navarro-Rosinés P, Roux C, Gueidan C. 2007 – La genroj Verrucula kaj Verruculopsis (Verrucariaceae, Verrucariales). Bull. Soc. Linn. Provence 58, 133–180.
Reichert I. 1921 – Die Pilzflora Agyptens. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie Heft 5/6, 598–727.
Roux C. 2007 – Likenoj de Okcidenta Eŭropo Suplemento 4a: eltiraĵoj 2 (extraits 2). Bulletin d’information de l’Association Française de Lichénologie 32 (2), 5–36.
Steiner J. 1896 – Beiträge zur Flechtenflora Südpersiens. Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften Math.-naturw. Klasse Abt. I. 105, 436–446.
Steiner J 1897 – Flechten aus Britiseh-Ostafrika. in,Sitzungsberichte Der Mathematisch-Naturwissenschaftlichen Class. 106, 207–234.
Vouaux L 1912a – Synopsis des champignons, parasites des lichens. Au siège de la société.
Entry by
Meng QF, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, 57100, Thailand and School of Public Health, Zunyi Medical University, Guizhou 563000, China.
Published online 30 June 2026