Halipegus eccentricus is a monoecious, digenea parasitic trematode commonly found in true frogs in North America.

The cercariae are cystophorous, while the metacercariae have two flame cells, a large acetabulum, and a spiny cuticula with eight pen-shaped apical hooks, which are used to penetrate the snail intestines.

Metamorphosed anurans become infected with H. eccentricus by feeding on metacercariae-infected damselflies or microcrustaceans (Cypridopsis sp.).

Inside of the snail intestine, the eggs undergo a series of development stages culminating in the cystophorous cercariae (32–35 DPE).

The cercariae pass into the feces and infect copepod and ostracod microcrustaceans, the second intermediate hosts, where they develop in the hemocel into metacercariae.