Fungalpedia – Note 2817, Amauroascus
Amauroascus. J. Schröt.
Citation when using this data: Kandemir H et al. 2022 – Fungalpedia.
Index Fungorum, Facesoffungi, MycoBank, GenBank
Classification: Onygenaceae, Onygenales, Eurotiomycetidae, Eurotiomycetes, Pezizomycotina, Ascomycota, Fungi
In addition to the type species of Amauroascus, the group included the type species of Brunneospora (B. reticulata), Byssoonygena (B. ceratinophila), Coccidioides (C. immitis) and Uncinocarpus (U. reesii).
The genus Amauroascus was found to be polyphyletic. Nomenclatural confusion about this genus goes back to 1893, when Schroeter described two new genera, Amauroascus and Arachniotus, at the same time (Schroeter 1893). In Amauroascus, he included Eidam’s Gymnoascus verrucosus (Eidam 1886; from moldy leather boots) and his own new species Amauroascus niger (Schroeter 1893; from old badger dung). The only criterion to differentiate between these two genera was the color of the ascospores. Since this is unfit for generic distinction, some researchers considered these two genera congeneric (Benjamin 1956; Kuehn 1958; Orr et al. 1965), whereas von Arx (1971) recognized Amauroascus as a separate genus and indicated A. verrucosus as a type species, albeit without an explanation. However, A. niger was already cited as the lectotype of the genus earlier (Clements and Shear 1954; Benjamin 1956), and it was suggested to follow this choice according to article 8.1 (ICBN) (Currah 1985).
Rammeloo (1982) compared the type specimens of Onygena mutata Quélet (1875; from the hoofs of an ox) and A. verrucosus (Eidam) Schroeter (1893; from moldy leather boots) and reported that the two species were identical, confirming the conclusions of Orr et al. (1965). However, he chose to change the name O. mutata to Amauroascus mutatus for the combined species. Since A. verrucosus was described earlier, it had priority over A. mutatus. Therefore, the following epitype is designated here for Amauroascus verrucosus: CBS 181.70, from soil, USA, G.F. Orr. This strain has an alternative collection number ATCC 22395.
Apinisia queenslandica (ex-type culture: CBS 280.77 = IMI 121675 = IFM 47370) was described from bird feathers in Australia by Apinis and Rees (1976). The species was subsequently placed in Uncinocarpus based on microscopic morphology (Sigler et al. 1998) and then moved to Amauroascus based on a higher ITS sequence similarity compared to Uncinocarpus reesii (Solè et al. 2002a). Solè et al. (2002a) synonymized Brunneospora reticulata (Guarro et al. 1987b; ex-type culture: FMR 784, from arable soil, Spain) and Orromyces spiralis (Ghosh and Sur, 1985; ex-type culture: GS-191, from soil, India) with U. queenslandica. These species are all keratinophilic and possess gymnothecia, helical peridial appendages, pigmented ascospores and chrysosporium-like anamorphs. The only difference mentioned in the description of the species was in terms of ascospore shape, i.e., globose in Apinisia, ellipsoidal in Brunneospora, oval in Orromyces and ovoid to globose in Uncinocarpus (Apinis and Rees 1976; Ghosh and Sur 1985; Guarro et al. 1987b; Solè et al. 2002a).
In the current study, Amauroascus verrucosus and Amauroascus niger grouped with U. reesii, whereas A. queenslandica and B. reticulata formed a separate. The similarity between A. queenslandica (ex-type culture: CBS 280.77) and B. reticulata (ex-type culture: UAMH 5704) was found to be 98% (in 546 bp). On the other hand, the similarity of Apinisia queenslandica (AJ390394) with U. reesii (NR_111092.1) and with A. niger (NR_159639.1) was 81%. Although the strain CBS 280.77 was first described as Apinisia, it was found to be placed far from the generic type, Apinisia graminicola (La Touche 1968; ex-type culture: CBS 721.68 on rotting Poaceae, UK).
For Orromyces, ex-type (GS-191) and isotype cultures (GS-141) of O. spiralis were reportedly deposited in the fungal herbarium of the Botany Laboratory, Department of Sciences, Regional College of Education, Bhubaneswar, Orissa (Ghosh and Sur 1985). However, we did not receive any response from the herbarium regarding the presence of this species, and no related information is available from other collections. Therefore, Orromyces spiralis is considered doubtful and has been abandoned.
Type species: Amauroascus verrucosus (Eidam) J. Schröt., in Cohn, Krypt.-Fl. Schlesien (Breslau) 3.2(1–2): 211 (1893) [1908].
Other accepted species: Species Fungorum – search Amauroascus.
References
Benjamin RK 1956 – A new genus of Gymnoascaceae with a review of the other genera. Aliso 3(3):301–328.
Benjamin RK 1956 – A new genus of Gymnoascaceae with a review of the other genera. Aliso 3(3):301–328.
Clements FE, Shear CL 1954 – The genera of fungi. Hafner, New York.
Currah RS 1985 – Taxonomy of the Onygenales: Arthrodermataceae, Gymnoascaceae, Myxotrichaceae and Onygenaceae. Mycotaxon 24:1–216.
Eidam E 1886 – Untersuchungen über die Femilie der Gymnoascaceen. Jahresbericht der Schlesischen Gesellschaft für Vaterländische Kultur 64:162.
Ghosh GR, Sur B 1985 – Keratinophilic fungi from Orissa, India III. Two new records. Kavaka 12(2):63–69.
Guarro J, Punsola L, Figueras MJ 1987b – Brunneospora reticulata, gen. et sp. nov. A keratinophilic ascomycete from Spain. Persoonia 13(3):387–390.
Kuehn HH 1958 – A preliminary survey of the Gymnoascaceae I. Mycologia 50(3):417–439.
Quélet L 1875 – Les champignons du Jura et des Vosges. Hachette Livre, Paris.
Schroeter J 1893 – Die Pilze Schlesiens. Fam. Gymnoascacei. In: Cohn F (ed) Krypt-Fl Schles 3(2), J.U. Kern’s Verlag, Breslau, pp 129–2.
von Arx JA 1971 – On Arachniotus and related genera of the Gymnoascaceae. Persoonia 6(3):371–380.
Entry by
Hazal Kandemir, Center of Expertise in Mycology, Radboud University Medical Center/Canisius Wilhelmina Hospital, Nijmegen, The Netherlands, Division of Medical Mycology, Faculty of Medicine, University of Cukurova, Adana, Turkey
Published online 25 June 2026