This article is a Validation List from the International Journal of Systematic and Evolutionary Microbiology that formally recognizes 14 new bacterial and archaeal species and 3 new genera that were previously published elsewhere. The validation list serves as the official mechanism for establishing nomenclatural validity in microbiology. The new taxa validated include species from diverse physiological groups: psychrophilic bacteria from tundra, thermophilic archaea from hot springs, anaerobic fermenters, purple nonsulfur bacteria, and organisms with specialized metabolic capabilities such as arsenic and selenium reduction. Each entry includes the proposed name, the original authors and references, priority number based on submission date, and nomenclatural type strain information with relevant culture collection accession numbers. The document clarifies that validation date is the publication date of this list, not the original publication date, and that inclusion validates the name for bacteriological nomenclature without necessarily implying taxonomic acceptance. The validated names enable proper scientific communication and prevent nomenclatural confusion in microbial taxonomy.

Key findings

• Fourteen new bacterial and archaeal species and three new genera were formally validated through this official IJSEM validation list
• Validated organisms represent diverse metabolic capabilities including thermophily, psychrophily, anaerobic fermentation, and reduction of arsenic and selenium oxyanions
• Validation date is established as the publication date of this list, retroactively formalizing names originally published in other journals
• All validated taxa include designated type strains deposited in international culture collections (ATCC, DSM, JCM, IFO) for scientific accessibility