On the occurrence of Abudefduf spp. (Pisces: Pomacentridae) in the Mediterranean Sea: a critical review with new records

Fishes of the genus Abudefduf are increasingly being recorded in Mediterranean waters, with most of these occurrences being based on the sole inspection of underwater images or video footage. Here we present a critical review of these occurrences, taking into account the uncertainties related to the identification of the congeneric A. vaigiensis and A. saxatilis, and testing the validity of the external traits used so far to distinguish these two species. After a careful revision of the Mediterranean literature and based on the analyses of images mostly taken in their natural native environment, we highlight the possibility that major morphological characters previously used to distinguish A. saxatilis from A. vaigiensis are not consistent within the species and thus not sufficiently reliable for their discrimination. This also relates to the possible confusion of these two species with a third species A. troschelii, never reported in the Mediterranean Sea to date. Finally, new records of the genus Abudefduf are reported for the Adriatic Sea and Tunisian waters.