borreliaceae borreliaceae the borreliaceae are a family of spirochete bacteria. borreliaceae scientific classification domain: bacteria phylum: spirochaetota class: spirochaetia order: spirochaetales family: borreliaceaegupta et al. 2014 genera borrelia swellengrebel 1907 (approved lists 1980) borreliella adeolu and gupta 2015 cristispira gross 1910 (approved lists 1980)