Mysids form an important part of the diet of such fish as shad and flounder.[2] In general, they are free-living, but a few species, mostly in the subfamily Heteromysinae, are commensal and are associated with sea anemones and hermit crabs.[5] Several taxa have also been described from different freshwater habitats and caves.[5] Mysis relicta and its close relatives inhabit cold, deep lakes and ha