Accacoeliidae is a family of trematodes (flukes) within the phylum Platyhelminthes, class Trematoda, and order Plagiorchiida. The family, which was established by Odhner in 1911, is sometimes classified under the superfamily Hemiuroidea within the suborder Hemiurata. It comprises several genera, including Accacladium, Accacladocoelium, Accacoelium, Odhnerium, Orophocotyle, Paraccacladium, Rhynchopharynx, and Tetrochetus.[1][2][3][4]
Members of the Accacoeliidae are parasitic in various fish species. Documented hosts include the ocean sunfish (Mola mola), the mahi-mahi (Coryphaena hippurus), the blotched river goby (Mogurnda variegata), and the picarel (Spicara maena). Specific species identified as parasites of these hosts include Odhnerium calyptocotyle, Accacladium nematulum, Accacladium serpentulum, and Accacoelium contortum. Occurrence data indicates a broad distribution range, spanning latitudes from -47 to 55 and longitudes from 90 to 375.[1][2]