A new species of Cruzia (Ascaridida; Kathlanidae) parasitizing Salvator merianae (Squamata, Teiidae) from the Atlantic forest in Brazil.

Cruzia lauroi sp. nov. is described from Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). The new species differs from all previously described species through several morphological characteristics: number of tooth like structures per row in the inner pharynx; and presence of unpaired papillae on the anterior border of the cloacal aperture. However, Cruzia lauroi sp. nov. is closest to C. tentaculata (Rudolphi, 1819), through having similar distribution of male caudal papillae, unpaired pre-cloacal papillae and females with an pre-equatorial vulva. Cruzia lauroi sp. nov. differs from C. tentaculata regarding smaller total body length of individuals, higher number of tooth like structures per row in the pharynx, greater size of diverticulum, smaller size of spicules and a more anterior vulva than in C. tentaculata; and the males do not have caudal alae. Cruzia mazza, C. travassosia, C. mexicana and C. testudines were considered to be species inquirendae, because their descriptions need more detailed taxonomic studies.