Fungalpedia – Note 2756, Arnium
Arnium. Nitschke ex G. Winter.
Citation when using this data: Huang SK et al. 2021 – Fungalpedia.
Index Fungorum, Facesoffungi, MycoBank, GenBank
Classification: Incertae sedis, Sordariales, Sordariomycetidae, Sordariomycetes, Pezizomycotina, Ascomycota, Fungi
Saprobic on wood, coprophilous. Sexual morph: Ascomata perithecial, scattered, superficial to semi-immersed, obpyriform to subglobose, membranaceous, pale brown to dark brown, ostiolate, with necks. Necks cylindrical to conical, black, glabrous or covered with unbranched, tapering, brown hairs, with hyaline, filiform periphyses. Paraphyses filiform to cylindrical, septate. Asci 8-spored, unitunicate, cylindrical to clavate, pedicellate, apex rounded, evanescent. Ascospores uni-seriate to irregularly arranged, obovoid to ellipsoidal to fusiform, aseptate, hyaline when young, becoming dark brown when mature, with ornamented wall and a gelatinous appendage at each end or surrounded by a gelatinous sheath. Asexual morph: Undetermined (adapted from Nitschke 1873; Lundqvist 1974).
Notes: Arnium is typified by A. lanuginosum and has subglobose ascomata, cylindrical to clavate asci and ascospores with a gelatinous appendage at each end (Nitschke 1873). Subsequently, A. lanuginosum was synonymized under Podospora brassicae (Ellis and Everhart 1892). This genus was rarely mentioned until it was clarified by Lundqvist (1972), and several Arnium species were then introduced (Cain and Mirza 1972; Krug and Cain 1972; Lundqvist 1974). Arnium species are phylogenetically scattered among the families of Sordariales, and several taxa have been transferred to Cladorrhinum, Podospora and Triangularia (Wang et al. 2019; Marin-Felix et al. 2020). In this study, Arnium species nested in Naviculisporaceae, Podosporaceae and Neoschizotheciaceae, but there is no molecular data for A. lanuginosum. Thus, we place the genus in Sordariales genera incertae sedis pending more data.
Type species: Arnium lanuginosum Nitschke [as ‘lanuginosa’], Bot. Ztg. 31: 450 (1873).
Other accepted species: Species Fungorum – search Arnium.
References
Cain RF, Mirza JH 1972 – Three new species of Arnium. Can J Bot 50:333–336.
Ellis JB, Everhart BM 1892 – The North American pyrenomycetes. A contribution to mycologic botany.
Krug JC, Cain FR 1972 – Additions to the genus Arnium. Can J Bot 50:367–373.
Lundqvist N 1972 – Nordic Sordariaceae s. lat. Symbolae Botanicae Upsalienses 20:1–374.
Nitschke TH 1873 – Flora oder Botanische Zeitung 31:450.
Entry by
Shi-Ke Huang, State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang 550025, China, The Engineering Research Center of Southwest Bio-Pharmaceutical Resources, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou Province, China, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand, The Mushroom Research Centre, Guizhou University, Guiyang 550025, China
Published online 18 June 2026