DNA barcoding revealing the mislabeling of fish in a highly tourist capital in Brazil

The consumption of raw fish has been increasing considerably in the West, since it has an appeal to be potentially healthier (omega 3 and 6, essential amino acids and vitamins). However this potential benefit, as well as the taste, value and even the risk of extinction is different between species of fish, constituting grounds for fraud. Through the Project "Cat by Hare", using the principles of the DNA barcode, we revealed mislabelling of fish in japanese restaurants and fishmarkets in Florianópolis, a highly tourist capital in Brazil. We sequenced the COI gene of 65 samples from fishmongers and 80 from restaurants and we diagnosed 34\% of fraud in fishmongers and 17\% in restaurants. This different percentage is related to the restaurants selling only two species (Tuna and Salmon) and one category of fish called "white fish" that can be any species that has whitish musculature. We discussed that frauds may have occurred for different reasons: to circumvent surveillance on threatened species; to sell fish with sizes smaller than allowed or species that are being highly captured as being a low captured one at any time (law of supply); to induce product consumption using species with better taste. It should be noted that some substitutions are derived from incorrect identification and are not a fraud per se, due to confusion of popular names or misunderstanding of sellers. Therefore, we suggest the implementation of a systematic regulatory program conducted by governmental agencies to reduce mislabelling to avoid further damage to the community (in health and financial issues) and fish stocks