TYGS
The pragmatic species concept for Bacteria and Archaea is ultimately based on DNA-DNA hybridization (DDH), a method known to be tedious. The GGDC (https://ggdc.dsmz.de) is a state-of-the-art in silico method for genome-to-genome comparison, thus reliably mimicking conventional DDH, except for its pitfalls. Its successor, the Type (Strain) Genome Server (TYGS) is a user-friendly high-throughput web server for genome-based prokaryote taxonomy. These services are accompanied by VICTOR (http://victor.dsmz.de/) for Virus phylogeny and classification and by a single-gene phylogeny service. The List of Prokaryotic names with Standing in Nomenclature (LPSN) provides comprehensive information on the nomenclature of prokaryotes and more.