First confirmed records of juvenile bigeye thresher sharks Alopias superciliosus in Patagonia, Argentina, and southward range extension in the southwestern Atlantic

Three juvenile specimens of Alopias superciliosus were recorded in Patagonia, Argentina, including one captured as bycatch in a bottom trawl fishery and two recovered following stranding events. These constitute the first confirmed records of the species in Patagonia and extend its known southern distribution in the southwestern Atlantic by approximately 1,345 km (9° 1′ 40″ of latitude). The presence of juvenile specimens on the Patagonian continental shelf raises the possibility that juveniles may occur in this region during part of their early life history, although the limited number of records precludes determining whether this reflects regular habitat use or only sporadic occurrence. These findings expand current knowledge of the distribution of A. superciliosus in the southwestern Atlantic and highlight the need for additional research on the occurrence and habitat use of pelagic sharks in Patagonia