A new species of <i>Stilestrongylus</i> (Nematoda, Heligmonellidae) from the Atlantic Forest of Misiones, Argentina, parasitic in <i>Euryoryzomys russatus</i> (Cricetidae, Sigmodontinae)

Abstract

A new species of Heligmonellidae (Trichostrongylina, Heligmosomoidea), <i>Stilestrongylus kaaguyporai</i> n. sp. is described from the small intestine of <i>Euryoryzomys russatus</i> (Rodentia, Cricetidae, Sigmodontinae) from the Argentine Atlantic Forest, in the Misiones province. The new species was found at Campo Anexo Manuel Belgrano, Reserva de Vida Silvestre Urugua-í and Parque Provincial Urugua-í, with a prevalence of 73% in 15 hosts examined. <i>Stilestrongylus</i> includes 24 Neotropical species, all parasitic in rodents, mostly Sigmodontinae. <i>Stilestrongylus kaaguyporai</i> n. sp. can be differentiated from its congeners by the following characters: caudal bursa dissymmetrical with right lobe larger and pattern of type1–4 in both lobes, rays 6 not forming a lateral trident with rays 4 and 5, rays 8 with dissymmetrical pathway, genital cone hypertrophied with a conspicuous hood-like projection and females with a marked dorso-ventral torsion of the posterior end. This report is the second record of a <i>Stilestrongylus</i> species in <i>E. russatus</i>, increasing to nine the number of parasitic species known from this host.