Species of Gorgoderina (Digenea: Gorgoderidae) in Rana vaillanti and Rana cf. forreri (Anura: Ranidae) from Guanacaste, Costa Rica, including a description of a new species.

Gorgoderina parvicava, G. diaster, and G. megacetabularis n. sp. are reported inhabiting the urinary bladders of Rana vaillanti and R. cf. forreri from northwestern Costa Rica. Gorgoderina megacetabularis n. sp. differs from all other species of the genus by the combination of the following characters: small body size (2.78-3.17, mean 2.92 mm), sucker ratio (1:3.1-3.7), and by the presence of 2 compact, oval, unlobed vitelline masses. Redescription of G. diaster including previously undescribed details on the reproductive apparatus and morphometric data is provided. This is the first record of the 3 species of Gorgoderina in Costa Rica and is the first record of G. diaster in R. vaillanti and R. cf. forreri.