Una nueva especie de Hassalstrongylus (Nematoda: Heligmonelidae) de Euryoryzomys russatus (Rodentia: Sigmodontinae) el la Mata Atlántica, Brasil

Hassalstrongylus luquei n. sp. is described from the small intestine of Euryoryzomys russatus (Rodentia: Sigmodontinae) collected in the Atlantic Forest (Rio de Janeiro State, Angra dos Reis, Brazil). The genus Hassalstrongylus includes 16 Neotropical species. The main characters of new species are subsymmetrical caudal bursa with a type 2-2-1, rays 8 branching at midlength of dorsal trunk, right lateral trunk larger than the left and the longest spicules in the genus. Only three species of Hassalstrongylus have the rays 8 not emerging at the base trunk, these are: H. mazzai; H. aduncus; and H. echalieri. However, the present species is distinguished from H. mazzai by having the dorsal rays divided at fourth part of the trunk, H. bocqueti by having rays 5 bifurcating at third part of trunk and H. echalieri by having a pattern of 2-2-1