LAUSR

During a survey of helminth parasites of the brown ground snake, Atractus major Boulenger, 1894 (Serpentes: Dipsadidae) from Moyobamba, region of San Martin (northeastern Peru), a new species of Glossidiella Travassos, 1927 (Plagiorchiida: Plagiorchiidae) was found and is described herein based on morphological and ultrastructural data. The digeneans found in the lung were measured and drawings were made with a drawing tube. The ultrastructure was studied using scanning electron microscope. Glossidiella peruensis sp. nov. is easily distinguished from the typeand only species of the genus, Glossidiella ornata Travassos, 1927, by having an oblong cirrus sac (claviform in G. ornata), distinctly ovate testes (rounded testes in G. ornata) and button-like papillae on the dorsal edge of the oral sucker region (absent in G. ornata). In addition, G. peruensis sp. nov. differs from G. ornata by possessing a longer distance between testes and substantially wider oral and ventral suckers. This is the first time that a species of digenean is described and reported parasitizing snakes in Peru.