Seven fungal strains labeled as one species reveal four lineages

A re-examination of seven public culture-collection strains filed under Pleurophragmium parvisporum found that they belonged to four distinct families or orders across three fungal classes. Only one strain conformed to the species concept of P. parvisporum and was designated its reference strain. The study, published in IMA Fungus , also identified several previously unrecognized lineages and showed how strains can be deposited under names that do not represent their true taxonomic placement.

This is particularly difficult for fungi with simple or convergent morphologies, in which organisms from different lineages can share outwardly similar features. When type material or authentic reference strains are unavailable, DNA barcodes cannot be compared directly with the deposit, leaving identification dependent on morphology. The researchers therefore combined cultivation experiments, comparative morphological analysis, biogeographic assessment and phylogenetic reconstruction using six nuclear markers.

Two strains were assigned to Thysanorea in the order Chaetothyriales, class Eurotiomycetes. One was described as the new species Thysanorea acropleurogena ; the other was a sterile strain identified as the previously known T. melanica . Two additional strains were placed in Wongia , within Papulosaceae of uncertain placement in class Sordariomycetes, and were introduced as W. pallidopolaris and W. rhachidophora .

The final two represented distinct novel taxa in the order Tubeufiales, class Dothideomycetes: Zaanenomyces hilifer and Skoliomycella flava , the latter a new genus as well as a new species. Thus, the seven deposits were not variations of a single recognized species but members of multiple fungal lineages distributed among four groups. The phylogenetic results also changed the broader classification of Pleurophragmium .

The species was resolved within Neomyrmecridium , order Myrmecridiales, class Sordariomycetes, leading the authors to reduce Neomyrmecridium to synonymy with Pleurophragmium . The revision produced 11 new combinations: P. asiaticum , P. asymmetricum , P. fusiforme , P. gaoligongense , guizhouense , P. luguense , P. naviculare , P. pteridophytophilum , P. septatum , P. sichuanense and P. sorbicola . Three species formerly classified in Uncispora were also transferred to Thysanorea as T. hainanensis , T. sinensis and T. wuzhishanensis , based on congruent morphological and multi-locus phylogenetic evidence.

The study’s central finding concerns the reliability of names attached to living reference material. Best practices for preserving fungal strains emphasize DNA barcodes and comprehensive metadata, but the authors note that the absence of type or authentic reference strains can prevent direct barcode comparison. The seven strains illustrate how misinterpretation of subtle morphological traits can result in misidentified material entering a public collection under an incorrect name, where it may perpetuate taxonomic errors.

The revision refined the generic limits of Pleurophragmium and morphologically similar genera, recovered previously unrecognised lineages and reassigned six of the seven examined strains away from P. parvisporum .

Subject of Research: Taxonomic re-examination of seven fungal strains publicly deposited under the name Pleurophragmium parvisporum

Article Title: Pleurophragmium parvisporum (Ascomycota): One name, seven stories – a case highlighting the need for verification of strains from public culture collections

Article References: Réblová, M., Nekvindová, J., Bauchová, L., & Hernández-Restrepo, M. (2025). Pleurophragmium parvisporum (Ascomycota): One name, seven stories – a case highlighting the need for verification of strains from public culture collections. IMA Fungus, 16, Article e173033. https://doi.org/10.3897/imafungus.16.173033

Image Credits: AI Generated

DOI: 10.3897/imafungus.16.173033

Keywords: fungal taxonomy, public culture collections, Pleurophragmium, DNA barcoding, multi-locus phylogeny, comparative morphology, Ascomycota, species identification, taxonomic revision, mycology, parvisporum, name