thiovulum majus thiovulum majus thiovulum majus is a species of bacteria and a member of the phylum campylobacterota. this sulfide-oxidizing species has been observed to swim at speeds as high as 615 micrometers per second, faster than those recorded for any other bacterial species. thiovulum majus scientific classification domain: bacteria phylum: campylobacterota class: "campylobacteria" order: campylobacterales family: helicobacteraceae genus: thiovulum binomial name thiovulum majus