Cardicola forsteri (Digenea: Sanguinicolidae) from the heart of a northern bluefin tuna, Thunnas thynnus (Scombridae), in the northwest Atlantic Ocean

We report a specimen of Cardicola forsteri Cribb, Daintith, and Munday, 2000 (Digenea: Sanguinicolidae) from the lumen of the heart of a northern bluefin tuna, Thunnus thynnus (Linnaeus, 1758) (Scombridae), that was 218 cm in total length (TL) and C caught in the northwest Atlantic Ocean 12 km South of Cape Lookout, North Carolina. The hearts of 12 similarly sized northern bluefin tuna (127-262 cm TL) front George's Bank, northwest Atlantic Ocean, were not infected. This is the first report of C. forsteri from a wild host and of a sanguinicolid from any scombrid in the northwest Atlantic Ocean. Bluefin tuna is cultured in sea cages because Of its highly prized flesh, and the fact that a blood fluke infects this host is significant because some blood flukes have been identified as serious pathogens of cage-cultured fish.