New species of Oswaldocruzia (Nematoda: Molineidae) in Ameiva festiva (Squamata: Teiidae) from Nicaragua

Oswaldocruzia ukrainae (Nematoda: Molineidae)-A Parasite of European Green Toad Bufotes viridis: Morphological and Molecular Data

Nematodes of the genus Oswaldocruzia are common parasites of the small intestine of amphibians and reptiles. Our recent molecular analysis of Oswaldocruzia nematodes revealed that only Oswaldocruzia filiformis, which possesses high morphological variability, parasitizes amphibians and reptiles in European Russia. Here we present the study of Oswaldocruzia nematodes from the European green toad Bufotes viridis (Anura, Bufonidae) collected at different localities of the Middle Volga region in 2018-2022. We analyzed the morphological characteristics of the Oswaldocruzia spp. taxonomy together with novel molecular phylogenetic data. The data on phylogenetic analysis (based on partial CoxI mtDNA gene sequences) showed that Bufotes viridis is parasitized by two Oswaldocruzia species, the host-specific parasite Oswaldocruzia ukrainae and species generalist Oswaldocruzia filiformis. Broad morphological variability was revealed in O. ukrainae nematodes both from the same host specimen and from various toad individuals from different localities. Our results highlight the need for further biodiversity research of morphologically similar Oswaldocruzia species from amphibians and reptiles in the Western Palearctic using molecular genetic methods.

NEW SPECIES OF RHABDIAS (NEMATODA: RHABDIASIDAE) AND OTHER HELMINTHS FROM NOROPS CAPITO (SAURIA: POLYCHROTIDAE) FROM NICARAGUA

Rhabdias nicaraguensis n. sp. (Rhabditida: Rhabditidae) from the lungs of Norops capito (Sauria: Polychrotidae) is described and illustrated. Rhabdias nicaraguensis n. sp. represents the 54th species assigned to the genus and the 12th from the Neotropical realm. Of the 12 Neotropical Rhabdias species, nicaraguensis is most similar to tobagoensis and vellardi. These 3 species have equatorial placement of the vulva, inflated cuticle, and 6 small circumoral lips. Rhabdias nicaraguensis is easily separated from R. tobagoensis by the shape of the buccal cavity and from R. vellardi by body size and shape of the tail. Rhabdias nicaraguensis differs from both species by host preference, the amount of inflated cuticle covering the body, and the phasmids situated posterior to the midpoint of the tail.