A New Species of Cryptocotyle (Digenea: Heterophyidae) Infecting Kelp Gull and a Galaxiid Fish in Patagonian Freshwater Environments: Morphological and Molecular Analyses

CASALINS, LAURA M.; ARBETMAN, MARINA P.; VIOZZI, GUSTAVO P.; FLORES, VERÓNICA R.

JOURNAL OF PARASITOLOGY

AMER SOC PARASITOLOGISTS

Año: 2020 vol. 106

0022-3395

Adults of a species of Cryptocotyle were found infecting the intestine of the kelp gull, Larusdominicanus Lichtenstein, 1823, and metacercariae were found in the fins and muscle of the galaxiidfish, Galaxias platei Steindachner, 1898 (local name ??puyen grande??), in Nahuel Huapi NationalPark (Patagonia). Morphometrics and genetic markers of mitochondrial cytochrome oxidase (COI)and ribosomal internal transcribed spacer 1 (ITS1) confirmed that adults and metacercariae wereconspecific and represent a new species, Cryptocotyle dominicana n. sp. The only congener knownfrom South America (Cryptocotyle thapari McIntosh, 1953) matures in river otters (Lutra spp. andPteronura spp.) in Brazil and Bolivia and differs from the new species in the arrangement of thetestes, which are located in tandem in the species from otters. Adults of the new species resembleCryptocotyle lingua (Creplin, 1825) Fischoeder, 1903 from marine environments of the NorthernHemisphere, both species being characterized by having a linguiform body, oblique testes, andvitelline follicles that extend posteriorly to the level of the ventral sucker. Considering themorphological findings that differentiate the new species from other Cryptocotyle, as well as themolecular analysis that shows significant differences from C. lingua, we conclude that thesespecimens represent a new species, the first of the genus Cryptocotyle to be described from birds inSouth America.