Aplectana uaehi n. sp., which inhabits the small intestine of Ambystoma velasci, the Plateau Tiger Salamander, collected from Lago de Tecocomulco, Hidalgo, Mexico, is described. This new species is distinguished from all other species of Aplectana in having 3 toothlike projections in the esophagus, each tooth bearing 3 ridges. The new species most closely resembles Aplectana hylambatis. The latter species also has 3 toothlike projections, but they are covered by a thick cuticle and each has a small cuticular spike that projects into the buccal cavity (Baker, 1980), features not present in members of Aplectana uaehi n. sp. In addition, the 2 species differ in the length of the spicules of males (240–350 µm vs. 320–520 µm, respectively) and the number of postcloacal papillae (4–6 pairs vs. 10 pairs, respectively). This record represents the first report of Aplectana in a member of the Order Caudata and is the first member of the genus found as a parasite of a species endemic to Mexico that is itself distributed in a restricted area of the Mexican Transition zone between the Nearctic and Neotropical regions.