The family liolopidae (Digenea) including a new genus and two new species from crocodilians

Abstract

Two new species of liolopid digeneans infecting crocodilians are described and the classification of the family slightly revised. Liolope copulans from the salamander Megalobatrachus japonicus in Japan actually possesses an internal rather than external seminal vesicle and tegumental spines, and the generic diagnosis is emended to include those features. Liolopids paratisitizing crocodilians are removed from Harmotrema and placed in a separate new genus characterized by the possession of a relatively short body with gonads in the posterior rather than middle third of the body. Liolopids infecting Neotropical lizards and turtles remain in Helicotrema and those parasitizing freshwater and marine snakes remain in Harmotrema. The first new species, from Alligator mississipiensis in the southeastern United States, most closely resembles the species described as Harmotrema rudolphii from a saltwater crocodile in the Philippines, but differs from it by having a shorter cirrus sac, stouter and shorter cirrus, and slightly smaller eggs; it differs from all crocodilian liolopids by possessing a more extensively folded metraterm. The second new species, from Crocodylus cataphractis in the Congo (Belgian), differs from all others in crocodilians by having a relatively larger pharynx and smaller acetabulum. Diagnoses of all crocodilian liolopids are presented. Harmotrema laticaudae, previously known from Laticauda laticaudata in Okinawa only, is reported from Aipysurus laevis, Hydrophis major, and a ‘black and white-ringed sea snake’ in Queensland, Australia.