A comprehensive phylogenetic analysis of Simulium (Psilopelmia) is made, using 67 of the 69 valid species and with indepth reinterpretation of comparative morphology. The analysis tested the monophyly of the subgenus, its species-groups, and evaluated the phylogenetic structure within them. The data matrix, composed by 87 terminal taxa and 73 characters obtained from adult, pupa, and larva, was analyzed under parsimony implied weighting, with a wide range of concavities. The searches found ten categories of k, grouped when they found the same MPTs, and the nodal stability was estimated via parameter sensitivity analysis. According to our results, Simulium (Psilopelmia) is monophyletic only if the species from the groups Blacasi and Oviedoi are excluded, as they fail to group with the remaining species-groups. Simulium (Psilopelmia), S.  (Notolepria), S . (Chirostilbia), and S . (Psilozia) form a clade, where S . (Psilopelmia) and S . (Psilozia) are sister-groups. Each of the species-groups of S . (Psilopelmia), Dinellii, Escomeli, Perflavum, and Romanai were recovered as monophyletic and stable, but Bicoloratum is not stable. The species-groups Callidum and Virescens were proposed to tentatively accommodate the species of S . (Psilopelmia) that did not fit into any of the traditional groups. We propose a new subgenus for Blancasi species-group, Simulium (Eremulium) subgen . n .

America continent, black fly, cladistics, Culicomorpha, implied weighting, Insecta, morphology, systematics, taxonomy