Fungalpedia – Note 2588, Pseudostigmidium
Pseudostigmidium Etayo
Citation when using this data: Meng QF et al. – Fungalpedia.
Index Fungorum, faceoffungi, MycoBank, GenBank, Fig 1.
Classification: Mycosphaerellaceae, Mycosphaerellales, Dothideomycetidae, Dothideomycetes, Pezizomycotina, Ascomycota, Fungi
Pseudostigmidium was established by Etayo et al. (2008c) to include five species characterized by small, black perithecia that are subconical or subglobose, often immersed and protruding from the lichen thallus. These fungi have eight-spored, bitunicate asci, and three-septate, hyaline spores. The type species, Pseudostigmidium nephromiarium, was originally described as Microthelia nephromiaria Linds. and later transferred by Vouaux (1913c) to Sphaerulina as S. nephromiaria (Lindsay) Vouaux (Lindsay 1869). Etayo et al. (2008c) reclassified this species into the newly established genus Pseudostigmidium and designated it as the type species.
Wijayawardene et al. (2022) listed Pseudostigmidium as a dubious genus within Mycosphaerellaceae due to the lack of confirmed phylogenetic placement based on DNA data. To date, five lichenicolous species are recognized in this genus.
Type species: Pseudostigmidium nephromiarium (Linds.) Etayo
= Microthelia nephromiaria Linds.
Other accepted species: Species Fungorum – search Pseudostigmidium
Figure 1 – Pseudostigmidium nephromiarium redrawn from Etayo et al. (2008c). a P. nephromiarium growing on host. b Peirphyses. c Asci. d Ascospores. Scale bars: a = 500 μm, b–d = 5 μm.
References
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 11 June 2026