- Volume 75, Issue 11, 2025

The species epithet Novosphingobium mangrovi Huang et al. 2023 is illegitimate under Rule 51b (5) of the International Code of Nomenclature of Prokaryotes, as it is a later homonym of Novosphingobium mangrovi Hu et al. 2023. The type strains of these two species share average nucleotide identity (84.7%; <95 %) and digital DNA–DNA hybridization (21%; <70 %) values below the recommended species delineation thresholds, substantiating their positions as two distinct species. Herein, the replacement name Novosphingobium mangrovisedimenti is proposed, preserving the original meaning related to the isolation of the type strain from mangrove sediments.

A novel ascomycetous yeast species of the genus Zygosaccharomyces is proposed, based on isolates obtained in Japan, Portugal and the USA, and on a combination of conventional DNA barcode sequence analyses and whole-genome phylogenies. The new species is described as Zygosaccharomyces progenitor sp. nov. (PYCC 7198T) and was found in association with bees (Apis mellifera and Bombus spp.) and their honey, besides being found in plants and soil. The novel species belongs to a Zygosaccharomyces subclade that also harbours Zygosaccharomyces rouxii. Although the two species can be differentiated at the sequence level, they cannot be distinguished at the phenotypic level. As is typical of the genus, Z. progenitor sp. nov. produces spherical ascospores after cell conjugation.

Two strains of Scopulariopsis-like fungi were isolated from the dorsal region of a live bat (Glossophaga soricina, nectarivore species) captured inside Gruta do Arnoud, a cave in the Caatinga biome of northeastern Brazil. These isolates presented unique morphological features, and achieving a consensus identification at the species level proved to be challenging. Phylogenetic analysis, based on nucleotide sequences from the internal transcribed spacer, large subunit ribosomal RNA gene, translation elongation factor 1-alpha (tef1) and beta-tubulin (tub2) genes, confirmed that these fungi represent previously undescribed species within the genus Microascus. The new species is named Microascus luziarum URM 9260. Phylogenetically, they grouped in a clade closely related to Microascus brunneosporus, Microascus micronesiensis and Microascus chinensis, but distinct differences were observed. Morphologically, the new species could be differentiated by their distinctive characteristics, such as reduced growth on oatmeal agar medium, reaching 15 mm after 14 days at 25 °C. Microscopically, it differs in the size of the conidiophores, which are shorter and broader compared to M. brunneosporus and M. micronesiensis. Additionally, it presents globose to subglobose conidia with diameters larger than those observed in closely related species. The use of a four-marker combination was an efficient approach to support the taxonomic novelty. This discovery enhances the understanding of Microascus diversity, particularly within cave ecosystems, and emphasizes the potential for discovering new fungal species in such specialized environments.

Three yeast strains closely related to the genus Vanderwaltozyma were isolated from rotting wood (Zelkova serrata) and soil in Japan. Based on sequence analyses of the internal transcribed spacer (ITS1–5.8S–ITS2) region, the D1/D2 domain of the LSU rRNA gene and the mitochondrial COX II gene, together with physiological characterization, these isolates were determined to represent a novel species. The ITS and D1/D2 sequences of the three strains were nearly identical, differing only by a single nucleotide, and their physiological profiles were indistinguishable, supporting their conspecificity. Notably, the strains actively fermented d-glucose and d-fructose. They exhibited tolerance to high osmotic stress, being capable of growth in media containing either 10% sodium chloride with 5% glucose or up to 50% (w/v) glucose. Furthermore, under V8 agar culture conditions, they consistently produced four ascospores per ascus. Phylogenetic analyses based on ITS and LSU D1/D2 sequences clearly placed these strains within the genus Vanderwaltozyma but distinct from other known species. In addition, comparison of COX II gene sequences further supported their separation from related species. Based on these phylogenetic and phenotypic characteristics, we propose Vanderwaltozyma osmotolerans sp. nov. to accommodate these isolates. The holotype of V. osmotolerans sp. nov. is designated as NBRC 117259T.

The bacterial order Enterobacterales has recently undergone major taxonomic revisions, with several new families and genera described. Within this framework, the rare genus Cedecea and the newly proposed genus Dryocola occupy closely related positions. The present study provides a comprehensive phylogenomic, phenotypic and functional assessment of Cedecea sulfonylureivorans LAM2020T and Dryocola clanedunensis H11S18T to clarify their taxonomic relationship. Genomic relatedness indices revealed high similarity between the two type strains, with average nucleotide identity, average amino acid identity and digital DNA–DNA hybridization values exceeding established species delineation thresholds. Phylogenetic analyses based on 16S rRNA, whole genomes and core gene sets consistently placed the two strains in a robustly supported monophyletic clade. These findings were further supported by shared metabolic and phenotypic traits. Taken together, the evidence demonstrates that C. sulfonylureivorans and D. clanedunensis represent members of the same biological species. Accordingly, and in line with Rule 42 of the International Code of Nomenclature of Prokaryotes, we propose the reclassification of C. sulfonylureivorans Li et al. 2024 as a later heterotypic synonym of D. clanedunensis Maddock et al. 2023. Furthermore, we propose two subspecies within this species: D. clanedunensis subsp. clanedunensis comb. nov. and D. clanedunensis subsp. sulfonylureivorans comb. nov.