arcanobacterium hippocoleae arcanobacterium hippocoleae arcanobacterium hippocoleae is a species of bacteria. it is a gram-positive, facultatively anaerobic, club-shaped (coryneform) species first isolated from a vaginal discharge of a horse. the type strain of a. hippocoleae is ccug 44697t (=cip 106850t). arcanobacterium hippocoleae scientific classification domain: bacteria phylum: actinomycetota class: actinomycetia order: actinomycetales family: actinomycetaceae genus: arcanobacterium species: a. hippocoleae binomial name arcanobacterium hippocoleaehoyles et al. 2002