Pleurophragmium fluviale Réblová & Hern.-Restr., 2025

Réblová, Martina, Nekvindová, Jana, Bauchová, Lucie & Hernández-Restrepo, Margarita, 2025, Pleurophragmium parvisporum (Ascomycota): One name, seven stories – a case highlighting the need for verification of strains from public culture collections, IMA Fungus 16, pp. e 173033-e 173033 : e173033-

Pleurophragmium fluviale Réblová & Hern.-Restr. nom. nov.

Basionym.

Myrmecridium aquaticum Z. L. Luo, K. D. Hyde & H. Y. Su , Fungal Diversity 99: 501. 2019.

Synonym.

Neomyrmecridium aquaticum (Z. L. Luo, K. D. Hyde & H. Y. Su) Crous , Persoonia 47: 201. 2021.

Etymology.

From Latin fluviale (“ of a river ” or “ riverine ”). Refers to the aquatic habitat from which the species was originally collected.

Typus.

CHINA • Yunnan Province, Lancang River ; saprobic on submerged decaying wood; Apr 2015; X. C. Tao S-448 ( holotype MFLU 18-1595 , isotype HKAS 92833 , ex-type culture MFLUCC 15-0366 = KUMCC 15-0340 ) .

Notes.

The protologue of P. fluviale (as M. aquaticum, Luo et al. 2019 ) included the ex-type strain MFLUCC 15-0366 and two paratype strains, MFLUCC 18-1489 = S-1158, and S- 001. In the original phylogenetic analysis, all three strains were resolved as conspecific. Myrmecridium aquaticum was later transferred to Neomyrmecridium by Crous et al. (2018 a), who treated P. guizhouense (as Neomyrmecridium guizhouense, Hyde et al. 2020 ) as its synonym, based on a phylogenetic analysis that included the ex-type strain of P. guizhouense ( GZCC 20-0008 ) and both paratype strains of P. fluviale . However, the ex-type strain of P. fluviale was not included in that analysis. In the present phylogenetic analysis (Fig. 1 ), which includes sequences from available ex-type and paratype strains of both species, P. fluviale and P. guizhouense are shown to represent distinct species.

The name P. fluviale is based on M. aquaticum , but the epithet ‘ aquaticum ’ is unavailable in this genus due to the prior valid publication of P. aquaticum ( Heredia et al. 2007) . Therefore, a new name is proposed for M. aquaticum .

Among Pleurophragmium species, P. fluviale shows some similarity to P. parvisporum in conidial morphology. However, it clearly differs in smooth-walled conidia that remain subhyaline at maturity, and longer conidiophores.

Figures

Figure 1. Maximum likelihood phylogenetic tree of the Myrmecridiales based on ITS – LSU DNA sequences. Names in bold indicate taxonomic novelties; strain with its accession number in bold and highlighted in violet colour was sequenced in this study; b = ex-type of Neomyrmecridium aquaticum; c = ex-type of Neomyrmecridium triseptatum. T and P denote ex-type and ex-paratype strains. Thickened branches indicate support ML BS = 100 % and PP values = 1.0. Branch support of nodes ≥ 70 % ML and ≥ 0.95 PP is indicated above or below branches. A hyphen (–) indicates values lower than 75 % ML BS or 0.95 PP.