Morphology and DNA analysis identify two new Veronaea species from Guizhou wood samples

A taxonomic study of four fungal isolates from decaying wood collected in Shuitian Town, Wudang District, Guizhou Province, China, identified two new species in the genus Veronaea: Veronaea guizhouensis and V. terrestris. The investigation combined detailed morphological observations with maximum-likelihood and Bayesian phylogenetic analyses of four DNA regions.

Veronaea belongs to the family Herpotrichiellaceae within the order Chaetothyriales. The genus was established with V. botryosa as its type species, which was originally isolated from a decayed palm rachis in Italy. Before the present findings, 28 species were accepted in the genus, but molecular data were available for only 14. Only the asexual morph had been documented, while the sexual morph remained unknown. The authors described these gaps in molecular sampling and sexual-stage data as hindering fuller assessment of the genus’s taxonomy, evolution and diversity.

The researchers collected decaying wood from freshwater and terrestrial habitats in Shuitian Town on 22 October 2025. The material was incubated in plastic boxes lined with moistened tissue at room temperature for one to two weeks and examined with a stereomicroscope. Conidiophores, conidiogenous cells and conidia were photographed with a compound microscope, and their dimensions were measured using Tarosoft Image Frame Work. Single spores were transferred to potato dextrose agar, where colony characteristics were documented after 31 to 35 days. Dried specimens and living cultures were deposited in the Herbarium of the Guizhou Academy of Agricultural Sciences and the Guizhou Culture Collection.

For the molecular analysis, genomic DNA was extracted from living cultures. The researchers amplified and sequenced the internal transcribed spacer region, large and small subunit ribosomal RNA genes, and the beta-tubulin gene, designated ITS, LSU, SSU and tub2. Sequences were checked and assembled in BioEdit and SeqMan, compared through BLASTn, aligned with MAFFT and inspected in AliView. After trimming with trimAl, the four loci were concatenated into a 3,047-character dataset representing 36 taxa. Maximum-likelihood analysis was conducted in IQ-TREE, while Bayesian inference used four simultaneous Markov chains for 10 million generations with 25% burn-in.

The maximum-likelihood and Bayesian analyses produced similar tree topologies and resolved the four isolates into two distinct Veronaea lineages. GZCC 25-27598 and GZCC 25-27599 formed a sister clade to V. pinangae, supported by an 88% maximum-likelihood bootstrap value and a Bayesian posterior probability of 0.95. GZCC 25-27600 and GZCC 25-27601 clustered with V. guizhouensis, V. pinangae and V. submersa while forming a separate lineage. The best-scoring maximum-likelihood tree had a final likelihood value of −11,467.306.

V. guizhouensis was described as saprobic on decaying wood in a freshwater habitat. Its branched conidiophores measured 177–209 μm, conidiogenous cells measured 39–63.5 μm, and conidia measured 7–14 × 2.5–5 μm; the conidia were cylindrical to pyriform and had one to three septa. Comparisons with V. pinangae showed differences in the lengths of the conidiophores, conidiogenous cells and conidia. The ex-type isolate GZCC 25-27598 differed from the ex-type isolate of V. pinangae by 13 of 407 base pairs in ITS, 6 of 904 in LSU and 43 of 375 in tub2, corresponding to 3.2%, 0.7% and 11.5%, respectively, with the reported gaps included.

V. terrestris was described from decaying wood in a terrestrial habitat. Its unbranched conidiophores measured 77–134 μm, conidiogenous cells measured 16–35 μm, and conidia measured 9–12.5 × 3–5 μm. Although its overall morphology resembled that of V. guizhouensis, its conidiophores and conidiogenous cells were shorter. The ex-type isolate GZCC 25-27600 differed from the ex-type isolate GZCC 25-27598 of V. guizhouensis by 17 of 409 base pairs in ITS, 11 of 894 in LSU, 4 of 1,018 in SSU and 56 of 484 in tub2, corresponding to 4.2%, 1.2%, 0.4% and 11.6%, respectively; the ITS comparison included five gaps and the tub2 comparison included nine.

The authors considered the addition of the two species evidence that submerged woody substrates can harbor previously undocumented fungal diversity and suggested that Veronaea richness in aquatic ecosystems is likely underestimated. Freshwater records of the genus remain comparatively scarce, with five species previously reported exclusively from submerged wood. With the two additions, the discussion counted 30 Veronaea species across Australia, Brazil, China, Egypt, India, New Zealand, North America, South Africa, Thailand and the United Kingdom. The present study was limited to four isolates from one locality and four loci, did not document a sexual morph and did not investigate the ecological roles of the new species.

Separate earlier work cited in the study reported cytotoxic metabolites from Veronaea and described moderate cytotoxic activity in V. brunneicolor against the human lung cancer cell lines H460 and A549, along with inhibitory activity against several plant-pathogenic fungi. The authors noted that the metabolic diversity and ecological roles of most Veronaea species remain largely unexplored. The new species were presented as taxonomic additions; the study did not test their secondary-metabolite profiles, pharmaceutical applications or agricultural effects.

Subject of Research: Taxonomic identification of two new Veronaea species from decaying wood in Guizhou, China

Article Title: Two new species of Veronaea ( Herpotrichiellaceae , Chaetothyriales ) from Guizhou Province, China

Article References: Zhang, W., Long, H., Liu, X., Song, X., Zhou, X., Zhang, Y., & Feng, Q. (2026). Two new species of Veronaea (Herpotrichiellaceae, Chaetothyriales) from Guizhou Province, China. MycoKeys, 139, 89-108. https://doi.org/10.3897/mycokeys.139.206673

Image Credits: AI Generated

DOI: 10.3897/mycokeys.139.206673

Keywords: Veronaea, fungal taxonomy, new species, Guizhou, China, molecular phylogeny, ITS LSU SSU tub2, freshwater fungi, morphology, species, Herpotrichiellaceae, Chaetothyriales