When some species, including Bathyctena chuni, Euplokamis stationis and Eurhamphaea vexilligera, are disturbed, they produce secretions (ink) that luminesce at much the same wavelengths as their bodies.
What do bathyctena chuni, euplokamis stationis and eurhamphaea vexilligera have in common?
they produce secretions (ink) that luminesce