First report of Genidens barbus during the non-reproductive period in coastal waters of Río Negro, Argentina

The marine catfish Genidens barbus is a benthic and anadromous species distributed from Brazil to southern Argentina. Its presence during the non-reproductive period remains poorly documented. This study reported the first confirmed record of a female G. barbus outside the reproductive season, which was incidentally caught in the artisanal Argentine red shrimp (Pleoticus muelleri) fishery off the coast of Río Negro, Argentina (41° 05′ S-64° 03′ W) at a depth of 70 m. This finding provides novel evidence for the Patagonian population, suggesting that the species may occupy deeper marine habitats during non-reproductive periods. The presence of P. muelleri in the stomach content reinforces its benthophagous feeding habit and trophic association with the coastal benthic community. This record expands the current knowledge of the seasonal and ecological distribution of G. barbus, as well as conservation strategies. Given its status as a vulnerable species and the limited information available on its behavior outside estuaries, this finding makes a significant contribution to our understanding of Patagonian ichthyofauna and the sustainable management of its populations.