Dactylogyrids (Monogenoidea: Polyonchoinea) parasitizing the gills of snappers (Perciformes: Lutjanidae): revision of Euryhaliotrema with new and previously described species from the Red Sea, Persian Gulf, the eastern and Indo-west Pacific Ocean, and the Gulf of Mexico

Twenty one of 29 species of snappers (Lutjanidae), examined for dactylogyrids (Monogenoidea) from the Red Sea, Persian Gulf, the Indo-west and eastern Pacific Ocean, the Gulf of Mexico, and Caribbean Sea were parasitized by 16 new and 11 previously described species of Euryhaliotrema: Euryhaliotrema adelpha sp. nov., Euryhaliotrema anecorhizion sp. nov., Euryhaliotrema cardinale sp. nov., Euryhaliotrema chrysotaeniae, Euryhaliotrema cognatus sp. nov., Euryhaliotrema cryptophallus sp. nov., Euryhaliotrema diplops sp. nov., Euryhaliotrema distinctum sp. nov., Euryhaliotrema fajeravilae sp. nov., Euryhaliotrema fastigatum, Euryhaliotrema fatuum sp. nov., Euryhaliotrema ferocis sp. nov., Euryhaliotrema hainanense, Euryhaliotrema longibaculum, Euryhaliotrema mehen comb. nov., Euryhaliotrema paracanthi, Euryhaliotrema paululum sp. nov., Euryhaliotrema perezponcei, Euryhaliotrema ramulum sp. nov., Euryhaliotrema seyi sp. nov., Euryhaliotrema simplicis sp. nov., Euryhaliotrema spirotubiforum, Euryhaliotrema tormocleithrum sp. nov., Euryhaliotrema torquecirrus, Euryhaliotrema tubocirrus, Euryhaliotrema xinyingense, and Euryhaliotrema youngi sp. nov. Six species of Euryhaliotrema, previously reported from lutjanid hosts, were not collected: Euryhaliotrema anguiformis comb. nov., Euryhaliotrema guangdongense, Euryhaliotrema johni, Euryhaliotrema lutiani, Euryhaliotrema lutjani, and Euryhaliotrema nanaoense comb. nov. The diagnosis of Euryhaliotrema was emended to include species having tandem or slightly overlapping gonads, a pretesticular germarium, a globose haptor with morphologically similar anchors and hooks, a coiled or meandering male copulatory organ, a dextral vaginal pore, and hooks with upright acute thumbs and slender shanks comprised of one subunit. A bulbous base of the MCO and presence of an accessory piece in the copulatory complex were no longer considered features defining the genus. As a result, Euryhaliotrematoides and Aliatrema were placed in subjective synonymy with Euryhaliotrema, and the following transfers were proposed: Euryhaliotrema annulocirrus comb. nov., Euryhaliotrema aspistis comb. nov., Euryhaliotrema berenguelae comb. nov., Euryhaliotrema cribbi comb. nov., Euryhaliotrema grandis comb. nov., Euryhaliotrema mehen comb. nov., Euryhaliotrema microphallus comb. nov., Euryhaliotrema pirulum comb. nov., and Euryhaliotrema triangulovagina comb. nov. In addition, the following new combinations were proposed based on the revised diagnosis of the genus: Euryhaliotrema anguiformis comb. nov., Euryhaliotrema eukurodai comb. nov., Euryhaliotrema kurodai comb. nov., Euryhaliotrema monoporosum comb. nov., and Euryhaliotrema nanaoense comb. nov. The dactylogyrids, Protancyrocephalus rangusi (from a lutjanid host) and Daitreosoma chaetodontis (from a chaetodontid host), were considered species inquirendae. Haliotrematoides tukerhamatus comb. nov. is considered the senior subjective synonym of Haliotrematoides nagabinae. New host records for some previously described species of Euryhaliotrema from lutjanid and chaetodontid hosts were reported.