colwellia psychrotropica colwellia psychrotropica colwellia psychrotropica is a psychrophilic antarctic bacterial species with the ability to synthesize docosahexaenoic acid. it is nonpigmented, curved-rod-like in shape, exhibiting facultative anaerobic growth and possessing an absolute requirement for sea water. its type strain is acam 179t. colwellia psychrotropica scientific classification domain: bacteria phylum: pseudomonadota class: gammaproteobacteria order: alteromonadales family: colwelliaceae genus: colwellia species: c. psychrotropica binomial name colwellia psychrotropicabowman et al. 1998