Thirteen new species and one new genus are described in the commensal amphipod family Anamixidae, bringing the total to 33 species in three genera. Thirteen species are recorded from the Pacific Ocean, eight from the Indian Ocean and four from the Caribbean. Developmental stages are documented in four species of Anamixis Stebbing, 1897 and one species of Nepanamixis n.gen. Developmental stages in Nepanamixis are profoundly different from those of Anamixis and Paranamixis Schellenberg, 1938. All new taxa are fully described and figured. Previously described taxa are reviewed and illustrated where necessary. The cryptic Anamixidae are found in coral reefs and other hard-bottomed, shallow, tropical waters. An unusual tropical relic, A. tangaroa n.sp., is described from cold waters in the Bass Strait, Australia. Current species distributions and information probably reflect collecting bias as many areas remain uncollected.
Cladistic analysis of the Anamixidae proved informative in the Nepanamixis-Anamixis group where adequate specimens of new and existing species were available for examination. Results were less informative for Paranamixis.