Fungalpedia – Note 2428, Minutisphaera
Minutisphaera. Shearer, A.N. Mill. & A. Ferrer.
Citation when using this data: Dong W et al. 2020 – Fungalpedia, Ascomycota.
Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig 1
Classification: Minutisphaeraceae, Minutisphaerales, Incertae sedis, Dothideomycetidae, Dothideomycetes, Pezizomycotina, Ascomycota, Fungi
Saprobic on submerged wood. Sexual morph: Ascomata scattered or clustered in groups, erumpent to superficial, uniloculate, globose to subglobose, brown, with central, rounded ostiole surrounded by black hairs. Peridium thin, composed of textura angularis to globulosa cells. Pseudoparaphyses sparse in young ascomata, becoming abundant with age, cellular, hyaline, septate, simple or branched, embedded in a gelatinous matrix. Asci 8-spored, bitunicate, fissitunicate, ovoid to obclavate, lacking a pedicel, rounded at the apex. Ascospores irregularly arranged, clavate, mostly straight, hyaline to pale brown, 1(–3)-septate, constricted at the septum, multiguttulate, asymmetrical, smooth- or rough-walled when mature, with sheath and filamentous appendages (Ferrer et al. 2011). Asexual morph: Undetermined.
Notes: All species reported within Minutisphaera were collected from freshwater habitats (Ferrer et al. 2011; Raja et al. 2013b, 2015; Bao et al. 2019a). The ascospores of Minutisphaera are unusual in being asymmetrical and often equipped with a sheath and filamentous appendages (Ferrer et al. 2011; Raja et al. 2015). The shape and size of ascospores, and features of appendages and sheaths are used for distinguishing all species within the genus.
In the analysis of Raja et al. (2015) BLAST search of ITS sequences revealed that two isolates, Pleosporales sp. 39g (JX244063) and Didymosphaeria sp. TS_04_050 (HQ713763), shared 99% similarity with Minutisphaera aspera. Both strains were isolated as fungal endophytes in previous studies (Grünig et al. 2011). Thus, it was hypothesized that members of Minutisphaerales may lead a dual life as saprobes on submerged wood and as fungal endophytes of trees living in close proximity to rivers and streams. However, additional studies are needed to shed light on the dual ecological life style of Minutisphaera spp.
Type species: Minutisphaera fimbriatispora Shearer, A.N. Mill. & A. Ferrer.
Other accepted species: Species Fungorum – search Minutisphaera.
Figure 1 – Minutisphaera spp. (Material examined: USA, North Carolina: Rockingham County, Piedmont Plateau, Big Beaver Island Creek, Madison, on submerged decorticated wood, 26 April 2013, H.A. Raja & N.H. Oberlies, G427-1, ILLS 72340, holotype; ibid., G156-4, ILLS 72342, paratype). a–c M. aspera (G427-1). a Ascoma on wood. b Ascus. c Ascospores. d–f M. parafimbriatispora (G156-4). d Ascoma in culture. e Asci. f Ascospore with gelatinous sheath constricted at the mid-septum. Scale Bars: a = 100 µm, b, c = 20 µm, d = 50 µm, e, f = 10 µm
References
Entry by
Wei Dong, Faculty of Agriculture and Food, Kunming University of Science and Technology, Kunming 650500, China, Department of Entomology and Plant Pathology, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Innovative Agriculture Research Center, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand, Institute of Plant Health, Zhongkai University of Agriculture and Engineering, Haizhu District, Guangzhou 510225, China
Published online 22 May 2026