Deciphering Magnivitellinum sp. (Digenea: Alloglossidiidae) from Salta, Argentina, with genetic markers.

JOSÉ D. SARAVIA; DORA DAVIES; CAROLINA DAVIES; FLORENCIA LIQUIN; JUAN JOSE LAUTHIER; HECTOR ANTONIO CRISTÓBAL

Congreso; Molecular Parasitology Meeting XXXI; 2020

The genus Magnivitellinum has been reported in the Neotropical region parasitizing characiform, siluriform and cyprinidontiform fish. To date, traditional ecological and morphological studies showed that there are 2 species in the genus: M. simplex (Kloss, 1966) and M. corvitellinum (Lacerda, Takemoto and Pavanelli, 2009). However, the morphological descriptions of the species many times are incomplete or unclear, and their genetic characterization has just recently started with a few sequences published belonging to M. simplex from Mexico. Adult and larval stages of specimens of this genus were found in different locations and hosts from Salta in northern Argentina. With the aim to determine whether they belong to one or multiple species of Magnivitellinum, ITS1, 28S and COI DNA sequences of these samples are being analyzed in parallel to morphological and ecological studies. Using primers published for Macroderoididae (Al Khandari et al., 2011), a 300 bp fragment was obtained for the ITS1 region from cercariae DNA, while the 1200 bp expected sequence was obtained for the 28S gene from adults and cercariae using primers published for M. simplex from Mexico (Hernandez Mena et al., 2016). No specific sequences were obtained using different sets of primers for COI. Maximum likelihood trees with 1000 bootstraps (MEGA X) of the 28S sequence showed that the specimens found in Salta grouped close to M. simplex from Mexico, but the 1.45% difference in their sequence identity suggests that they belong to a different species. Similar results were obtained with the ITS1 fragment, with the individuals from Salta grouping alone in a branch between Alloglossidium sp. and Plagiorchis sp. The lack of results for the COI gene highlights the absence of nucleotide sequences in GenBank for close relatives of Magnivitellinum, and in general, the need of more studies on species from South America to widen the range of genetic sequences available for comparisons. Together with ecological and morphological data, these results suggest that the specimens of Magnivitellinum found in Salta, Argentina belong to a new species.