Identification of a non-native Cynoscion species (Perciformes: Sciaenidae) from the Gulf of Cádiz (southwestern Spain) and data on its current status




biological invasion, marine introduction, weakfish, Cynoscion regalis, Guadalquivir estuary, taxonomy


Cynoscion is a genus of fish in the family Sciaenidae from the Atlantic and Pacific American coasts that is important in recreational and commercial fisheries. Morphological analysis identifies a species inhabiting the Gulf of Cádiz (southern Spain) as the weakfish, Cynoscion regalis, a native of the northwest Atlantic. This finding is also confirmed by molecular identification using 16S and Cox1genes. Based on the examination of a previous manuscript, the assignation of this species to the spotted seatrout, Cynoscion nebulosus, is considered a misidentification. C. regalis has been reported in the area since 2011 and is now considered an established species that is distributed along the Guadalquivir River estuary and is a target of local artisanal fisheries. The pathway of introduction is unknown, but possible mechanisms are considered, of which ballast water seems to be the most plausible. A revision of non-native sciaenids also found in European waters is carried out. The ecological impact of weakfish on the local fish community is still unknown and should be object of future studies.


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How to Cite

Bañón R, Arias A, Arana D, Cuesta JA. Identification of a non-native Cynoscion species (Perciformes: Sciaenidae) from the Gulf of Cádiz (southwestern Spain) and data on its current status. Sci. mar. [Internet]. 2017Mar.30 [cited 2024May27];81(1):19-26. Available from:




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