First record of the Atlantic spadefish Chaetodipterus faber (Broussonet, 1782) in the Mediterranean Sea: is it a new aquarium release?

The Atlantic spadefish Chaetodipterus faber (Broussonet, 1782) belongs to the family Ephippidae Bleeker, 1859 and is a widely distributed species in the Western Atlantic. In this work we present the record of a single specimen of C. faber captured by a professional fisher in Argosaronikos Gulf, Greece. The present sighting, reported through the citizen science project "Is it Alien to you? Share it!!!", constitutes the first record of this species in the Mediterranean Sea. Given the distance from the Strait of Gibraltar and the absence of any report from western Mediterranean and eastern Atlantic countries, we argue that the specimen is likely to have been released from an aquarium hobbyist. With this record, a total of 27 alien fish species have been likely introduced in the Mediterranean through this pathway, all after year 2000. An increasing trend has been observed and we urge national authorities and relevant stakeholders for their cooperation on increasing the awareness of aquarium trade industry, while we also highlight the effectiveness of citizen science as an early warning system for alien species in the Mediterranean.