In a previous study, an isolate identified as Akanthomyces sensu lato, obtained from the citrus blackfly Aleurocanthus woglumi in Brazil, was shown to be pathogenic towards its host. Phylogenetic evidence indicated that this isolate belongs to a new taxon. This study aimed to describe this new taxon based on both morphological and molecular phylogenetic markers, to assess its potential for the biological control of the conehead termite (Nasutitermes corniger) and the citrus orthezia (Praelongorthezia praelonga) and to evaluate substrates for the mass production of this fungus. Phylogenetic analysis based on TEF1, RPB1, RPB2 and ITS partial sequences demonstrated that this new species is related to Lecanicillium aranearum, Lecanicillium araneicola, Lecanicillium rasoulzarei and Lecanicillium spenceae. However, these species form a clade that corresponds to neither Akanthomyces sensu stricto nor Lecanicillium sensu stricto. Therefore, a new genus Allolecanicillium is proposed here to accommodate Allolecanicillium elzae sp. nov., Allolecanicillium aranearum comb. nov., Allolecanicillium araneicola comb. nov., Allolecanicillium rasoulzarei comb. nov. and Allolecanicillium spenceae comb. nov. These species produce dense white to cream mycelia and simple or branched conidiophores bearing cylindrical to fusoid conidia. The sexual morph is known only for the species A. aranearum. Sporulation of A. elzae on vegetable substrates ranged from 1.46×10[8] conidia/g of substrate (white rice) to 6.42×10[8] conidia/g of substrate (sugarcane bagasse). Germination rates did not differ significantly among substrates. Despite being pathogenic to P. praelonga and N. corniger, this fungus showed relatively low virulence against these insects under the conditions tested. This research expands our knowledge of the diversity of entomopathogenic fungi, their host spectrum and alternatives for their production, aiming to foster the recognition of these organisms as sustainable biological resources.

Two alphaproteobacterial strains, designated EGI L300112[T] and EGI L300120, were isolated from sediment collected from Chaiwopu Lake in Xinjiang, China. The taxonomic position of the two strains was determined using polyphasic taxonomic analysis and phylogenomic analysis. Based on 16S rRNA gene sequence similarities, strain EGI L300112[T] and EGI L300120 were both closely related to Pelagerythrobacter rhizovicinus AY-3R[T] and shared the highest sequence identities of 96.2% and 96.3%, respectively. However, phylogenetic analysis based on the 16S rRNA gene and genomes clearly demonstrated that the two strains formed a distinct clade with validly published species of the genus Altererythrobacter. Furthermore, the two strains exhibited distinct phenotypic, physiological and genotypic characteristics that differentiate them from other related type species of the genus Altererythrobacter and related species in the family Erythrobacteraceae. Cells of the two strains were aerobic, Gram-stain negative, non-motile and rod-shaped. Optimal growth conditions for EGI L300112[T] and EGI L300120 occurred on marine agar 2216 at pH 7 at 30 °C. The major respiratory quinone was Q-10. The detected polar lipids of two strains included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylcholine and unidentified phospholipids. The major fatty acids (>10%) were identified as summed feature 3 (C16 : 1 ω7 c/C16 : 1 ω6 c) and summed feature 8 (C18 : 1 ω7 c). The G+C content of strain EGI L300112[T] and EGI L300120 was 61.2% and 61.4%, respectively. Based on differential phenotypic and genotypic characteristics of the two strains and related species in the genus Altererythrobacter, the two strains should be classified as representing a new species of this genus, for which the name Altererythrobacter chaiwopuensis sp. nov. is proposed. The type strain is EGI L300112[T] (=MCCC 1K09432[T]=KCTC 8712[T]).

The ascomycete genus Taphrina comprises dimorphic plant-parasitic pathogens, several species of which cause plum pockets. Plum pocket pathogens on Japanese plum (Prunus salicina) were collected from seven localities in Korea, including Gimcheon (KCTC 37381[T]/KACC 411123), Gumi, Okcheon (KCTC 37382/KACC 411126), Boeun, Jeonju, Wanju (KACC 410969) and Naju (KCTC 37383/KACC 411129). Based on a polyphasic approach combining morphological and physiological characterization with a molecular phylogenetic analysis involving the internal transcribed spacer (ITS) region, the D1/D2 domain of the 26S rRNA gene and the mitochondrial small subunit ribosomal RNA (rns) gene, these isolates were confirmed to represent a novel Taphrina species. Phylogenetically, the novel species was closely related to a clade comprising Taphrina pruni and Taphrina mume, which cause plum pocket disease and apricot leaf curl, respectively. Compared with the type strain of T. pruni (HA 1306ᵀ), the new Korean isolates exhibited low sequence similarity, with 95.79%, 98.95% and 98.77% identities in the ITS, D1/D2 domain and rns regions, respectively. Isolates infecting P. salicina formed an independent clade distinct from all known Taphrina species. The isolates also differed from T. pruni in ascospore size, budding rate within asci and cultural characteristics. Physiologically, the isolates differed from T. pruni HA 1306ᵀ in 7 of 41 carbon assimilation tests, 4 of 10 nitrogen assimilation tests, and growth at 25 ℃. To date, plum pocket pathogens on P. salicina have been attributed to T. pruni, Taphrina communis and Taphrina deformans; however, the present study shows that they represent a novel species. We propose the name Taphrina neopruni sp. nov. (MycoBank number MB 862651) and designate KCTC 37381[T] (ex-type strain KACC 411123) as the holotype.

Five Gram-negative strains, designated BI01[T], BI02, BI1211, BI4D and BI67 isolated from the gut of the Antarctic endemic insect Belgica antarctica, were characterized by a polyphasic approach. Comparative 16S rRNA gene sequences indicated that the bacterial strains belonged to the genus Yersinia. A cgMLST-based phylogeny based on 500 concatenated core genes strongly supported a clade encompassing the 5 strains that was distinct from the currently recognized 27 species of the genus Yersinia. Average nucleotide identity (ANI) among the five strains consistently exceeded 99%, but comparisons to their closest relative, Yersinia intermedia, yielded an ANI of 93% and a digital DNA-DNA hybridization value of 51.74. Metabolic profiling further differentiated the five strains from other closely related species within the genus Yersinia, notably with respect to l-fucose and potassium 2-ketogluconate fermentation, acetoin production and an absence of pyrazinamidase activity. Interestingly, three of the five strains exhibited resistance to β-lactams (amoxicillin and amoxicillin/clavulanate) and first- and second-generation cephalosporins (cefalexin and cefoxitin) associated with the presence of the ampC gene, encoding a class C beta-lactamase, in their genome. None of the five isolates harbour the classic virulence determinants of enteropathogenic Yersinia. The DNA G+C content of the five strains is 47.8 mol%. Based on these results, they represent a novel species of the genus Yersinia, for which the name Yersinia antarctica sp. nov. is proposed. Notably, this represents the first Yersinia species reported from Antarctic terrestrial invertebrates. The type strain is BI01[T] (=CIP 112622[T]=DSM 121309[T]). The distribution of this species is not limited to Antarctica, as few publicly available genomes indicate its presence in continental Russia and the Russian Arctic, with isolates recovered from rodents, polar bears and birds.

Two Gram-stain-positive, catalase-positive, oxidase-negative, non-spore-forming, aerotolerant anaerobic and non-motile short rod-shaped bacterial strains, designated V947[T] and V970, were isolated from nasal swab samples of coal miners. Phylogenetic analyses based on 16S rRNA gene sequences and whole-genome sequences revealed that strains V947[T] and V970 represent a distinct lineage within the genus Cutibacterium, most closely related to Cutibacterium avidum ATCC 25577[T] (16S rRNA gene sequence similarity of 97.09%). Whole-genome comparative analyses showed that the average nucleotide identity values between the two strains and all validly published species of the genus Cutibacterium with correct nomenclature ranged from 76.55 to 90.26%, while the digital DNA-DNA hybridization values ranged from 21.80 to 40.40%, both of which are well below the accepted thresholds for species delineation. Pangenome analysis identified 711 species-specific gene clusters present in strains V947[T] and V970 but absent from all reference type strains of the genus, which were predominantly involved in carbohydrate transport and metabolism, inorganic ion transport and signal transduction mechanisms, suggesting distinct metabolic capabilities and potential for environmental adaptation. These genomic features not only support the delineation of a novel species but also expand the known genomic and functional diversity within the genus Cutibacterium. The predominant cellular fatty acids were iso-C15:0 and anteiso-C15:0. The major polar lipids of strain V947[T] were diphosphatidylglycerol, phosphatidylinositol and phosphatidylcholine, and the predominant menaquinones were MK-8(H4) and MK-9(H6). On the basis of phylogenetic, genomic, chemotaxonomic and phenotypic characteristics, strains V947[T] and V970 represent a novel species of the genus Cutibacterium, for which the name Cutibacterium nasicola sp. nov. is proposed. The type strain is V947[T] (=CGMCC 1.5844[T]=KCTC 59608[T]).

Strain 17KM0847[T], isolated from the nasal discharge of a dead captive Cape ground squirrel (Xerus inauris), is a Gram-positive, oxidase-negative, catalase-positive and coagulase-negative coccoid bacterium. It grows under both aerobic and anaerobic conditions at 37 °C and tolerates up to 17.5% NaCl, and its colonies are smooth, convex and circular and exhibit complete staphylococcal α-haemolysis on sheep and horse blood agar. Phylogenomic analysis based on DNA alignment and amino-acid alignment obtained from the translated whole-genome sequence, along with comparisons of 16S rRNA and housekeeping genes (hsp60, dnaJ, rpoB, sodA, gap and tuf), placed strain 17KM0847[T] within the genus Staphylococcus, most closely related to species of Staphylococcus muscae, Staphylococcus microti, Staphylococcus rostri and Staphylococcus americanisciuri. The strain exhibited digital DNA-DNA hybridization (dDDH) values ≤22% and average nucleotide identity (ANI) values <78% to these closest relatives, well below the species-level delineation thresholds (70% dDDH; 95% ANI). Chemotaxonomic analysis identified diphosphatidylglycerol, phosphatidylglycerol and an aminophospholipid as the major polar lipids. The cellular fatty acid profile was dominated by C20 : 0, iso-C15 : 0, C16 : 0 and C18 : 0. The peptidoglycan contained type A3αl-Lys-Gly4-l-Ser-Gly. Based on chemotaxonomic and genomic characteristics, strain 17KM0847[T] (=DSM 120281[T]; =CCOS 2136[T]; =CCM 9521[T]) represents a novel species of the genus Staphylococcus, for which the name Staphylococcus xeri sp. nov. is proposed.

Two Gram-stain-negative, non-motile and oval-shaped bacterial strains, designated 2E107[T] and 2E233[T], were isolated from the brown alga Saccharina japonica collected in Rongcheng, Weihai, China (122° 33' E 37° 15' N). The two strains shared 98.0% 16S rRNA gene sequence similarity. Both strains grew at 4-37 °C, with optimum growth at 35 °C, and tolerated 0.5-10% (w/v) NaCl. Strain 2E107[T] grew at pH 6.5-9.5, with optimum growth at pH 7.0 and 1.5% (w/v) NaCl, whereas strain 2E233[T] grew at pH 5.5-9.0, with optimum growth at pH 6.5 and 4% (w/v) NaCl. Strain 2E107[T] produced melanin, whereas strain 2E233[T] was non-pigmented. The genomic DNA G+C contents of strains 2E107[T] and 2E233[T] were 62.8 and 60.5 mol%, respectively. In both strains, summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) was the predominant cellular fatty acid, and ubiquinone-10 was the sole respiratory quinone. The major polar lipids of strain 2E107[T] were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine and an unidentified lipid, whereas those of strain 2E233[T] were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid. The average nucleotide identity and average amino acid identity values between strain 2E107[T] and Pacificoceanicola onchidii XY-301[T] were 78.5 and 81.8%, respectively, whereas the corresponding values between strain 2E233[T] and P. onchidii XY-301[T] were 76.4 and 78.6%, respectively. On the basis of phylogenetic, phylogenomic, phenotypic and chemotaxonomic evidence, strains 2E107[T] and 2E233[T] are considered to represent two novel species of the genus Pacificoceanicola, for which the names Pacificoceanicola niger sp. nov. and Pacificoceanicola algae sp. nov. are proposed, respectively. The type strains are 2E107[T] (=MCCC 1H01529[T]=KCTC 8819[T]=SDUM152014[T]) and 2E233[T] (=MCCC 1H01530[T]=KCTC 8818[T]=SDUM152015[T]), respectively. Furthermore, on the basis of phylogenomic and comparative taxonomic evidence, Tropicibacter oceani Zhou et al. 2025 is proposed to be reclassified as Pacificoceanicola oceani comb. nov.

Two novel aerobic, Gram-stain-positive, endospore-forming and short rod-shaped bacterial strains, designated as sgz500922[T] and sgz5001074[T], were isolated from paddy soils in Fujian, PR China. The taxonomic position of two strains was determined using polyphasic taxonomy and phylogenomic analysis. Phylogenetic analysis and 16S rRNA gene sequence comparisons revealed that strains sgz500922[T] and sgz5001074[T] formed a distinct clade with Gorillibacterium massiliense G5[T] and shared sequence similarities of 96.3 and 93.5%, respectively. The average nucleotide identity value between the two strains and their closest reference strain was 73.1 and 72.3%, below the species threshold value of 95.0-96.0%, while the average amino acid identity values between sgz5001074[T] and G. massiliense and Paenibacillus contaminans were 62.4 and 63.2%, respectively. Optimal growth conditions of strains sgz500922[T] and sgz5001074[T] were pH 7.0 and 30 °C on Reasoner's 2A agar. Major fatty acids of sgz500922[T] and sgz5001074[T] were anteiso-C15:0 and C16:0. The main polar lipids included diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Both strains contained nitrogenase core gene nifHDK in their genomes, and nitrogenase and total nitrogen accumulation estimated their nitrogen-fixing ability. According to the phenotypic, genotypic and phylogenetic data, strains sgz500922[T] and sgz5001074[T] represent two novel species of the family Paenibacillaceae, for which the names Gorillibacterium terrae sp. nov. and Oryzibacillus soli gen. nov., sp. nov., respectively, were proposed (sgz500922[T]=MCCC 1K09374[T]=KCTC 43730[T], sgz5001074[T] (=MCCC 1K09398[T]=KCTC 43742[T]).

Six Streptomyces strains were isolated from scab-infected potato tubers collected in the province of Quebec, Canada. All isolates produced disease symptoms characteristic of potato common scab. Multilocus sequence analysis showed that the strains clustered into two putative novel species-level groups represented by strains LBUM1542[T] and LBUM3076[T]. Strains LBUM1542[T] and LBUM3076[T] shared the highest 16S rRNA gene sequence similarity with Streptomyces rishiriensis NBRC 13407[T] (99.73%) and Streptomyces acidiscabies ATCC 49003[T] (99.67%), respectively. Genome-based taxonomic analyses, including digital DNA-DNA hybridization and average nucleotide identity, supported the delineation of two novel species. Comparative genomic analyses revealed that both strains lacked the thaxtomin biosynthetic gene cluster classically associated with potato common scab but possessed other virulence determinants. Their predicted carbohydrate-active enzyme repertoires also differed markedly from those of their closest relatives. Morphological and phenotypic characteristics, together with genome-based chemotaxonomic predictions, were consistent with assignment to the genus Streptomyces. Some phenotypic traits, such as carbon source utilization, distinguished each strain from its closest phylogenetic neighbours. Taken together, these results demonstrate that LBUM1542[T] and LBUM3076[T] represent novel species, for which the names Streptomyces borealis sp. nov. (LBUM1542[T]=NCPPB 4834[T]=NRRL B-65796[T]) and Streptomyces saintjeani sp. nov. (LBUM3076[T]=NCPPB 4835[T]=NRRL B-65797[T]) are proposed.

The taxonomic boundaries of Pseudomonas moraviensis remain unclear despite the increasing availability of genomic data. In this study, we performed a comprehensive polyphasic taxonomic reassessment of 30 publicly available strains, together with 2 newly isolated wheat rhizosphere strains, S9433 and S9602, which exhibited genomic and phenotypic traits indicative of plant growth-promoting potential. Phylogenetic and phylogenomic analysis consistently revealed that strains currently assigned to P. moraviensis are distributed across several distinct lineages. Overall genomic relatedness indices, including average nucleotide identity (ANIb) and digital DNA-DNA hybridization (dDDH), supported the reclassification of multiple strains into different Pseudomonas species. Twenty-two strains including S9433 and S9602 were confirmed as P. moraviensis, whereas five were reclassified as Pseudomonas atacamensis, two as Pseudomonas parakoreensis and one as Pseudomonas iranensis. Strain #71, formerly designated as the type strain of P. moraviensis subsp. stanleyae, formed a distinct phylogenetic lineage with ANIb and dDDH values below species delineation thresholds and a divergent fatty acid profile, collectively indicating that it represents a novel species. Strain VanB exhibited ambiguous genomic relatedness to Pseudomonas aphyarum, Pseudomonas paraglycinae and Pseudomonas fitomaticsae, with ANIb values approaching but dDDH values well below species delineation thresholds, leaving its taxonomic status unresolved pending further investigation. This study clarifies and resolves the taxonomic status of currently assigned P. moraviensis strains and lays a foundation for the functional characterization and applied utilization of this species complex.

This article represents the valid publication of the names of three subspecies of Treponema pallidum. These subspecies were first described by Robert M. Smibert in 1984 and correspond with organisms that cause syphilis (subsp. pallidum), yaws (subsp. pertenue) and bejel (subsp. endemicum) in humans. The subspecies nomenclature has been widely used in the literature since that time but has not been validly published due in part to the availability of only limited genetic information. The designation of these subspecies is now supported by a large number of genomic sequences indicating a clear separation of these three closely related yet genetically distinct groups, as demonstrated in this study by phylogenetic analysis of a representative group of strains from each subspecies and the closely related lagomorph pathogen Treponema paraluiscuniculi. Subspecies-specific regions were also identified by genomic comparisons to provide an additional means of distinguishing the T. pallidum subspecies and T. paraluiscuniculi without complete genomic sequencing. Finally, the GauthierT (=BEI Resources NR-60826T=DSM 120346T) and Bosnia AT (=BEI Resources NR-60824T=DSM 120347T) strains are herein designated as the type strains of T. pallidum subsp. pertenue and T. pallidum subsp. endemicum, respectively, whereas NicholsT (=BEI Resources NR-59701T=DSM 117211T) and SS14 (=BEI Resources NR-60825=DSM 120345) represent type and reference strains of T. pallidum subsp. pallidum, respectively. Overall, this article corroborates the many prior reports that support the formal establishment of the three T. pallidum subspecies and provides additional guidelines for their distinction.

Five crocodilian species were investigated for the presence of Pasteurellaceae. A total of 27 pharyngeal isolates were obtained and characterized by MALDI-TOF MS and preliminary phenotypic tests to enable selection of representative strains for further genotypic characterization. Twelve isolates were selected for sequencing followed by phylogenetic analyses, digital DNA-DNA hybridization (dDDH) and calculation of average nucleotide identity (ANI), in addition to comparative analyses of partial rpoB, 16S rRNA gene sequences and further phenotypic characterization. The phenotypic and genotypic comparisons grouped the strains into three clades (clade 1: n=4; clade 2: n=3; clade 3: n=5). The clade 3 strains had a 16S rRNA gene sequence similarity ranging from 94.8 to 96.5%, a dDDH value of ≤48.7% and an ANI value of ≤92.6% to the closest relative, Testudinibacter aquarius ELNT2x[T], and could be distinguished from all current Pasteurellaceae species by a combination of phenotypic traits. Our results indicate that the clade 3 strains should be classified as representatives of a new Testudinibacter species for which we suggest Testudinibacter crocodili sp. nov. The type strain of T. crocodili is Cuba42[T] (=CCUG 77853[T]=DSM 118260[T]) and was isolated in Denmark in 2018 from the pharynx of a captive Cuban crocodile (Crocodylus rhombifer).