摘要：Twenty-four worms were collected from the bronchioles in both lungs of a male nine-banded armadillo Dasypus novemcinctus Linnaeus, 1758 captured in Teacalco, Morelos, Mexico. The worms, herein named Metathelazia mexicana n. sp., show a constriction in the esophagus at the level of the nerve ring; males of the species have 7 pairs of papillae, fewer than the other species in the genus. Metathelazia capsulata is the most similar species to Metathelaziamexicana; however, the latter has much shorter spicules. This is the fourth species in the genus known to occur in the New World.
