arthrobacter echini arthrobacter echini arthrobacter echini is a gram-positive, strictly aerobic and non-motile bacterium species from the genus arthrobacter which has been isolated from the gut of the sea urchin heliocidaris crassispina from dokdo island, korea. arthrobacter echini scientific classification domain: bacteria phylum: actinomycetota class: actinomycetia order: micrococcales family: micrococcaceae genus: arthrobacter species: a. echini binomial name arthrobacter echinilee et al. 2016 type strain am23dsm 29493kacc 18260