rickettsia peacockii rickettsia peacockii rickettsia peacockii is a species of gram negative alphaproteobacteria of the spotted fever group, identified from rocky mountain wood ticks (dermacentor andersoni). its type strain is skalkahot. the organism is passed transstadially and transovarially, and infections are localized in ovarial tissues. rickettsia peacockii scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: rickettsiales family: rickettsiaceae genus: rickettsia species group: spotted fever group species: r. peacockii binomial name rickettsia peacockiiniebylski et al., 1997