EXPLORANDO CORRELACIONES ENTRE DATOS BIOMETRICOS DE CNESTERODON DECEMMACULATUS Y SUS INFECCIONES PARASITARIAS: CONOCIENDO LA ABUNDANCIA, RIQUEZA DE ESPECIES Y DIVERSIDAD

YASMIN CROCI; MARTIN ACOSTA ALBARRACIN; MACARENA DE MARTINO; JORGE BARNECHE; SERGIO R. MARTORELLI; MARTIN MIGUEL MONTES

Congreso; XI Congreso Internacional de Parasitología Neotropical; 2023

In freshwater bodies of Argentina, seasonal variation in parasitism has been more studied in turtles and snails than in fish hosts. To improve the knowledge of this subject, the present study was focused on the parasitic fauna of Cnesterodon decemmaculatus (Cyprinodontiformes: Poeciliidae) from a partially protected stream. It is an ovoviviparous, omnivorous and non-migratory fish occurring at high densities in subtropical reservoirs of South America. The study was conducted in Juan Blanco Stream located in The Southern Coastal Park Biosphere Reserve. The stream dissipates in a wetland at the end of its route within the coastal plain of the Río de la Plata and most of the time it does not exceed the levee that separates it from it. It has a basin of 115 km2 which mostly presents extensive livestock with 14% of cultivated area and a length of approximately 29 km. A total of 238 fish were collected with cast nest for each season between winter 2018 to autumn 2019. A complete parasitological analysis of the fish was carried out with the determination of the total length (TL), and sex. Mean abundance, richness and diversity index were calculated for each sample. Changes in abundance were analyzed using the Kruskal Wallis test. Spearman's rank correlation coefficient (rs) was calculated to determine possible correlations between the host's total length and parasite´s abundance. We found six parasite taxa represented by: larvae of Echinostomatidae (Stephanoprora sp.) in gill filaments, larvae of Heterophyidae in gill filaments (Ascocotyle sp.1), heart arterial bulb (Ascocotyle sp.2), muscles (Ascocotyle sp.3), adults of Haploporidae (Saccocoelioides kirchneri) and adults of Neoechinorhynchidae (Wolffhugelia matercula) in the digestive tract. The abundances of Stephanoprora sp and Saccocoelioides kirchneri were different (p