asticcacaulis biprosthecum asticcacaulis biprosthecum asticcacaulis biprosthecum is a stalked bacterial species phylogenetically closely related to the species caulobacter crescentus. however, instead of a single polar organelle called the stalk, asticcacaulis biprosthecum possesses two stalks that are laterally positioned along the cylindrical cell body. the ecological significance of this arrangement is unknown. asticcacaulis biprosthecum scientific classification domain: bacteria phylum: pseudomonadota class: alpha proteobacteria order: caulobacterales family: caulobacteraceae genus: asticcacaulis species: a. biprosthecum binomial name asticcacaulis biprosthecumpoindexter 1964