PRESENCIA E INTENSIDAD DE LERNAEA CYPRINACEA (COPEPODA: CYCLOPOIDA) EN PECES DE LA PAMPA, ARGENTINA

YASMIN CROCI; MACARENA DE MARTINO; JORGE BARNECHE; SERGIO R, MARTORELLI; MARTIN MIGUEL MONTES

Conferencia; XI Congreso Internacional de Parasitología Neotropical; 2023

The introduction of exotic species is one of the most important causes of biodiversity loss. This is due to the phenomena of predation and competition and to the co-introduction of pathogens that later spread to the native fauna. Lernaea cyprinacea (Linnaeus, 1758), known commonly as anchor worm, is a species of copepod native to Eurasia that has adapted to a parasitic lifestyle. Its introduction to various parts of the world can be primarily attributed to the trade of cyprinid fish species. Consequently, reports of its presence have been documented in regions such as North America, South America, Europe, Asia, southern Africa, and Australia. Although there are studies on the presence of L. cyprinacea in other hosts in Argentina, they do not address aspects of ecology or records of this parasite in a protected area. Streams of the Parque Costero Sur Biosphere Reserve have not been properly studied in terms of interaction, composition, and ichthyfaunistic exchanges and the influence of the Río de la Plata. The aim of the present work was to examine the presence of L. cyprinacea in Psalidodon rutilus (Jenyns,1842) and Cheirodon interruptus (Jenyns,1842). The study was conducted in Juan Blanco Stream located in The Southern CoastalPark Biosphere Reserve. A total of 359 specimens of P. rutilus and 321 specimens of C. interruptus werecollected with cast nets for each season between winter 2018 and summer 2020. Fishes were examined for the investigation of crustacean parasites under a stereoscopic binocular microscope. Parasite metazoans were observed in vivo, counted, and preserved in 90% alcohol or fixed in 10% formalin. The prevalence, mean abundance, and intensity were calculated for each sample. Changes in prevalence were analyzed using the x2 test and a posteriori multiple comparisons to test for significant differences between seasons. A total of 59 copepods were found on P. rutilus sampling. Seasonal prevalence was different (x2 =35.9, p