[2] Boreomysinaes show wide diversity in the structure of eyes, from rather reduced to large with well-developed cornea.

[4] Being an ancient group of crustaceans,[5] possibly originated in the beginning of Mesozoic era, boreomysines are considered living fossils.

[8] Uropodal exopod with incomplete proximal suture, its segment 1 bearing distolateral spiniform setae;[10] endopod entire, without signs of articulation.

[10] Some authors suggested the suborder or the full family status for boreomysines, but only the subfamily level rank is currently supported.

[10] According to molecular genetic studies, Boreomysinae form a monophyletic clade, basal to most of Mysidae, and somewhat close to Rhopalophthalminae, also with articulated uropodal exopod and organic statolith.

[15] A detailed comparison suggests them to be structurally more similar to Siriellinae, sharing uropodal exopod articulation, its armature, non-differentiation of pereopods, non-reduction of pleopods and their apical modification.

[16] For example, Neobirsteiniamysis inermis is a rare case of bipolar amphitropical species, found in the deep water from Arctic to Antarctic.