When feeding they are sometimes accompanied by a species of shrimp, Periclimenes imperator, in an apparent form of commensalism.
The Emperor shrimp, Periclimenes imperator, is a commensal that is commonly found living on Hexabranchus sanguineus.
Imperator Aleksandr II-class battleship | ''Imperator Aleksandr II''-class | Imperator | Russian battleship Imperator Nikolai I | Periclimenes imperator | ''Imperator Nikolai I'' | Russian battleship Imperator Aleksandr III | Russian battleship ''Imperator Aleksandr III''' | Battleship ''Russian battleship Imperator Aleksandr III | Ave Imperator, morituri te salutant |