This species has an unusual larval stage, the mesocercaria, which accumulates in the second intermediate host, a tadpole. Normally the parasite passes through the metaceraria stage during a tissue migration in its definitive host, a terrestrial carnivore. This parasite uses a variety of paratenic hosts to enhance transmission between tadpole and carnivore. The mesoceraria simply penetrates the tissues of the paratenic host and remains as a mesocercaria. Paratenic hosts can accumulate large numbers of mesocercariae. Humans can act as a paratenic host as well, and have acquired serious infections by eating undercooked frog legs, with mesocercariae infecting such tissues as lung and eyes. This genus possesses a glandular tribocytic organ on the ventrum of the fore-body.