Fungalpedia – Note 2813, Spiromastigoidaceae
Spiromastigoidaceae. Guarro, Cano & Stchigel.
Citation when using this data: Kandemir H et al. 2022 – Fungalpedia.
Index Fungorum, Facesoffungi, MycoBank, GenBank
Classification: Onygenales, Eurotiomycetidae, Eurotiomycetes, Pezizomycotina, Ascomycota, Fungi
Spiromastix was originally described as a member of the family Gymnoascaceae, with the type species Spiromastix warcupii (Kuehn and Orr 1962). It was found to be unique because of its curved but never completely coiled peridial appendages (Kuehn and Orr 1962). However, since the name Spiromastix had already been applied to algae (Perfil’ev 1929), it was changed to Spiromastigoides by Doweld (2013). Rizzo et al. (2014) proposed the order “Spiromastix ales” (orthographic variant) based on LSU D1-D2 sequence analysis. The species have discrete or confluent, brown asco mata covered with orange-brown, curved or twisted append ages; eight-spored, subglobose, ovoid to ellipsoidal asci; and smooth-walled, yellowish to pale brown ascospores (Rizzo et al. 2014). However, Hirooka et al. (2016) reduced this to the family level as Spiromastigaceae in Onygenales using ITS and concatenated 18S + 28S data. This conclusion was supported by Stchigel et al. (2017), who changed the fam ily name to Spiromastigoidaceae because of its link with Spiromastigoides. Since Spiromastigoidaceae is typified with the type genus Spiromastigoides, it is maintained here. In the current study, the family comprises the genera Sigle ria, Spiromastigoides and Pseudospiromastix, as reflected in our LSU and multilocus data analyses, although with ITS data, Sigleria grouped separately, close to Clade 14. All members of Spiromastigoides are known to be cel lulolytic and nonkeratinolytic, except Spiromastigoides pyr amidialis, which has been reported to be weakly keratino lytic (Currah 1994; Hirooka et al. 2016). Human and animal infections have been suggested for S. albida and S. asexualis because of culture from biopsy specimens, and they are con sidered potential opportunistic pathogens (Rizzo et al. 2014; Stchigel et al. 2017). While all members of the genus have hemolytic and urease activity, only S. albida and S. asexu alis also have lipolytic activity (Stchigel et al. 2017; Rizzo et al. 2014). Phylogenetically, these two species are placed far apart, suggesting that lipolysis emerged more than once during the separation of the species or that it might be an atavism.For two species, S. saturnispora (Uchiyama et al. 1995b, ex-type culture: CBM BF54422, from meadowy soil, Indo nesia) and S. sphaerospora (Udagawa and Uchiyama 1999b; ex-type culture: SUM 3128, from sports field, Japan), mate rial was not available for study (Hirooka et al. 2016). The asexual morph of Spiromastigoides was reported in the literature either as malbranchea- or chrysosporium-like (Hirooka et al. 2016). During our analyses, the type strain of Malbranchea gypsea, CBS 134.77, was found among Spiromastigoides species. This strain was reported to be cel lulolytic, not keratinolytic, and it was recovered from lesions on the spleens and livers of mice after experimental pas sages (Orr 1972; Sigler and Carmichael 1976). Rodríguez Andrade et al. (2021) proposed Spiromastigoides gypsea for M. gypsea. Spiromastigoides gypsea (Sigler & Carmichael) Stchigel, Rodr.-Andr. & Cano – IMA Fungus 12: 25, 2021. Basio nym: Malbranchea gypsea Sigler & Carmichael—Myco taxon 4(2): 455, 1976; ex-type culture: CBS 134.77 = ATCC 35432 = UAMH 1975, Herb. IMI 211203 from soil, USA, G.F. Orr, 1964. A strain deposited as Chrysosporium pseudomerdarium (CBS 279.77) in the CBS collection by J.W. Carmichael was found in Clade 11; however, the ex-type culture of this species (CBS 631.79 = IMI 282432) clusters out side Spiromastigoidaceae (Tanney et al. 2015). Similarities between ITS and LSU loci of S. warcupii (CBS 576.63) and C. pseudomerdarium CBS 279.77 were found to be 94% and 97%, respectively. Therefore, CBS 279.77 was provisionally identified as Spiromastigoides sp. Sigleria Hirooka, Tanney & Seifert—Mycologia 108(1): 140, 2016; type species: Sigleria carmichaelii Hirooka, Tanney & Seifert; ex-type culture: CBS 138264 = DAOM 250076, from house dust, Micronesia. The genus Sigleria is represented by two species, Sigle ria amendiana (Hirooka et al. 2016; ex-type culture: CBS 138357 = DAOM 588476) and Sigleria carmichaelii. Both species were isolated from house dust. Although they are morphologically similar to Spiromastigoides species, con idiophores of Sigleria tend to show opposite branching, whereas Spiromastigoides species have a predominantly unilateral branching pattern (Hirooka et al. 2016). The most distinguishing characteristic of Sigleria is its limited ability to utilize nitrate as a nitrogen source. Furthermore, growth rates on malt extract agar (MEA) are slow, and ascomata have not been observed (Hirooka et al. 2016). Morphologi cal differences between the two genera were supported by phylogenetic results. Interestingly, S. car michaelii was often found to co-occur with Wallemia species on MEA with high sugar content (Hirooka et al. 2016).
Type genus: Spiromastigoides Doweld, Index Fungorum 30: 1 (2013).
References
Currah RS 1994 – Peridial morphology and evolution in the prototunicate ascomycetes. In: Hawksworth DL (ed) Ascomycete systematics: problems and perspectives in the nineties. Plenum Press, New York, pp 281–293.
Doweld A (2013) Index Fungorum 30:1
Kuehn HH, Orr GF 1962 – A new genus of Gymnoascaceae. Mycologia 54(2):160–167.
Orr GF 1972 – Recovery of several arthroaleuriosporous fungi from mice following intraperitoneal inoculation. Technical Report Desert Test Center, Dugway, DTC Proj. No. TN-72–542.
Perfil’ev BW 1929 – Spiromastix verrucosus nov. g.n.sp.n.fam. – Vertreter eines neuen Typus der Flagellaten. Mikrobiologicheskii Zhurnal (Leningrad) 9:132–137.
Sigler L, Carmichael JW 1976 – Taxonomy of Malbranchea and some other Hyphomycetes with arthroconidia. Mycotaxon 4(2):349–488.
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