Exopod of 1st pereopod, as a rule, well-developed. Carpopropodus of endopods of 3rd to 8th pereopods divided into subsegments. Marsupium of 2 or 3 pairs of oostegites, except in the subfamily Boreomysinae, which has 7 pairs of oostegites. Statocyst present on endopod of uropods. Most mysid species (over 90%) belong to this family. Includes 6 subfamilies.