The stygobiont gammarids of Haiti are more diversified than anywhere else in the world: not less than 13 species (all new) in 7 genera (5 new) and 4 subgenera (all new) are described of a somewhat loosely delimited group called the hadzioids/weckelioids. Practically all species have limited ranges within Haiti, whose stream systems apparently have acquired a great deal of isolation. The morphology of these amphipods makes even more indefinable the various supra-generic units proposed in the last 10 years for the “Gammaridae s.l.”