First report of lionfish prey from Western Florida waters as identified by DNA barcoding.

DNA barcoding was used to identify prey fragments recovered from the stomachs of lionfish harvested during the 2016 Sarasota Lionfish Derby. A total of 305 prey fragments were recovered from 50 stomachs (mean = 4.6 per stomach), of which 184 (60.3%) fragments could be identified to either species or genus when Cytochrome Oxidase I (COI) sequences were queried against the Barcode of Life Database. We identified 21 fish prey species which represented fourteen families and accounted for 95.7% of genetically identifiable prey items. The remaining prey items identified corresponded to six crustacean species. The four most common prey taxa in lionfish stomachs were (24.3%), an unidentified species (20.4%), (14.3%), and (12.2%). The most frequently observed crustacean species, , was found in only three stomachs (6.1%). We also report eleven taxa as putative novel lionfish prey species, most of which are common in Florida waters. Sixteen prey items were identified as lionfish (); however, it was not definitive whether these detections were due to cross contamination or cannibalization. This represents the first report of lionfish diets from Florida waters in the Eastern Gulf of Mexico based on barcoding efforts. Our results are largely congruent with previous COI barcoding based studies of lionfish diets, indicating these predators to be generalists exhibiting preferences for specific prey traits but with regional differences in their diets.