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A Gram-stain-negative, obligatory anaerobic spirochaete (RCC2812 T ) was isolated from a faecal sample obtained from an individual residing in a remote Amazonian community in Peru. The bacterium showed highest 16S rRNA gene sequence similarity to the pig intestinal spirochete Treponema succinifaciens (89.48 %). Average nucleotide identity values between strain RCC2812 T and all available Treponema genomes from validated type strains were all <73 %, thus clearly lower than the species delineation threshold. The DNA G+C content of RCC2812 T was 41.24 mol%. Phenotypic characterization using the API-ZYM and API 20A systems confirmed the divergent position of this bacterium within the genus Treponema . Strain RCC2812 T could be differentiated from the phylogenetically most closely related T. succinifaciens by the presence of alkaline phosphatase and α -glucosidase activities. Unlike T. succinifaciens , strain RCC2812 T grew equally well with or without serum. Strain RCC2812 T is the first commensal Treponema isolated from the human faecal microbiota of remote populations, and based on the collected data represents a novel Treponema species for which the name Treponema peruense sp. nov. is proposed. The type strain is RCC2812 T (=LMG 31794 T =CIP 111910 T ).