Aestuariibacter is a genus in the class Gammaproteobacteria (Bacteria), composed of four species, namely A. aggregatus, A. halophilus, A. litoralis and the type species A. salexigens.These are strictly aerobic marine rod-shaped bacteria.[1] They share many traits with the sister genus Alteromonas, the type genus of the family (Alteromonadaceae) and order (Alteromonadales).
The name Aestuariibacter derives from the Latin noun aestuarium, a tidal flat (the part of the sea coast which, during the flood-tide, is overflowed, but at ebb-tide is left covered with mud or slime) and the Neo-Latin masculine gender noun bacter, bacterium and thus means a tidal-flat bacterium,[1] as three species, except A. halophilus from the Yellow sea, were isolated in tidal flats.