Canonical discriminant analysis accurately separated males of Lutzomyia yencanensis (n = 36) (Ortiz), Lutzomyia cayennensis cayennensis (n = 24) (Floch and Abonnenc) and Lutzomyia micropyga (n = 28) (Mangabeira). Only seven (length of head, interocular distance, wing vein δ, genital filaments, coxite, paramere, and lateral lobe) of 20 possible morphometric measurements were required for differentiation, with a highly significant canonical correlation. The discriminant equations provided a simple, fast, and widely available statistical tool to identify accurately unknown sand fly specimens as L. yencanensis, L. c. cayennensis, or L. micropyga.