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Two Corynebacterium species were proposed decades ago, isolated from clinical samples and divided into biovars: "Corynebacterium genitalium" biovars I-V and "Corynebacterium pseudogenitalium" biovars C1-C6. Several biovars have been re-classified as new species. Nevertheless, biovar I and C5, together with their respective specific epithets "Corynebacterium genitalium" and "Corynebacterium pseudogenitalium", remained not validly published after more than 40 years. Several more strains, temptatively classified as "C. genitalium" biovar I and "Corynebacterium pseudogenitalium" C5, have been isolated from clinical and environmental samples. Both species presented Gram-positive, non-spore forming rod-shaped cells, able to grow aerobically with CO 2 . Core-genome analysis identified "C. genitalium" to be most closely related to Corynebacterium tuscaniense, Corynebacterium urinipleomorphum, Corynebacterium aquatimens and C appendicis, and Corynebacterium gottingense as the most closely related species to "C. pseudogenitalium". Comprehensive genomic, genotypic, phenotypic analyses, as well as chemotaxonomic, support the proposal for "C. genitalium" and "C. pseudogenitalium" as distinct species within the genus Corynebacterium. The designated type strains of the two species are Furness 392-1 T  = ATCC 33030 T  = CCUG 38989 T  = CCM 9178 T  = DSM 113155 T for C. genitalium sp. nov., nom. rev., and Furness 162-C2 T  = ATCC 33039 T  = CCUG 27540 T  = CCM 9177 T  = DSM 113154 T for C. pseudogenitalium sp. nov., nom. rev., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2022 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

Clinical and environmental-associated strains (n=17), genotypically related to Corynebacterium spp., yet distinct from any species of the genus Corynebacterium with validly published names, have been isolated during the last 20 years and tentatively identified as Corynebacterium sanguinis, although the combination, "Corynebacterium sanguinis" was never validly published. The comprehensive genotypic and phenotypic characterisations and genomic analyses in this study support the proposal for recognizing the species within the genus Corynebacterium, for which the name, Corynebacterium sanguinis sp. nov., is reaffirmed and proposed. Strains of Corynebacterium sanguinis are Gram-positive, non-motile, non-spore-forming, short, pleomorphic and coryneform bacilli, growing aerobically, with CO 2 . They contain mycolic acids, major respiratory menaquinones, MK-8 (II-H 2 ) and MK-9 (II-H 2 ), and polar lipids, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphoglycolipid, glycolipids and a novel lipid that remains to be characterized and identified. Strains of Corynebacterium sanguinis are genotypically most similar to Corynebacterium lipophiliflavum, with 16S rRNA gene sequence similarities of 98.3% and rpoB sequence similarities of 94.9-95.2%. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis were able to clearly differentiate Corynebacterium sanguinis from the most closely related species. The genome size of Corynebacterium sanguinis is 2.28-2.37Mbp with 65.1-65.5mol% G+C content. A total of 2202-2318 ORFs were predicted, comprising 2141-2251 protein-encoding genes. The type strain is CCUG 58655 T (=CCM 8873 T =NCTC 14287 T )., (Copyright © 2019 The Authors. Published by Elsevier GmbH.. All rights reserved.)

A novel Gram-positive, non-motile, non-spore-forming and aerobic bacterium, designated strain VA37-3 T , was isolated from a marine sediment sample collected at 19.2 m water depth from Valparaíso bay, Chile. Strain VA37-3 T exhibits 97.6 % 16S rRNA gene sequence similarity to Corynebacterium marinum D7015 T , 96.4 % to Corynebacterium humireducens MFC-5 T and 96 % to Corynebacterium testudinoris M935/96/4 T ; and a rpoB gene sequence similarity of 85.1 % to Corynebacterium pollutisoli VMS11 T , both analyses suggesting that strain VA37-3 T represents a novel species of Corynebacterium. Physiological testing indicated that strain VA37-3 T requires artificial sea water or sodium-supplemented media for growth, representing the first obligate marine actinomycete of the genus Corynebacterium. The genome of the proposed new species, along with the type strains of its most closely related species were sequenced and characterized. In silico genome-based similarity analyses revealed an ANIb of 72.8 % (C. marinum D7015 T ), ANIm of 85.0 % (Corynebacterium mustelae DSM 45274 T ), tetra of 0.90 (Corynebacterium callunae DSM 20147 T ) and ggdc of 24.7 % (Corynebacterium kutscheri DSM 20755 T ) when compared with the closest related strains. The genomic DNA G+C content of strain VA37-3 T was 57.0 %. Chemotaxonomic assessment of strain VN6-2 T showed the major fatty acids were C18 : 1ω9c and C16 : 0. Menaquinones predominantly consisted of MK-8(II-H2). Polar lipids consisted of diphosphatidylglycerol, glycolipids, phosphatidylglycerol, phosphoglycolipid and phosphatidylinositol. Mycolic acids also were present. Overall, the results from phylogenetic, phenotypic and genomic analyses confirmed that strain VA37-3 T represents a novel species of the genus Corynebacterium, for which the name Corynebacterium alimapuense sp. nov. is proposed, with VA37-3 T as the type strain (=CCUG 69366 T =NCIMB 15118 T ).