Claim: The Oscillibacter valericigenes' closest cultured relatives are Clostridium orbiscindens and Clostridium viride; additionally, it also exhibits a close relationship to Oscillospira guillermondii.
Evidence: Its closest cultured relatives at the time of its original description in 2007 were Clostridium orbiscindens (found in human feces) and Clostridium viride. It also exhibits a close relationship to Oscillospira guillermondii, a large bacterial species found in the guts of ruminant animals, which has yet to be grown in culture despite having been first observed in 1913.