The first snail host is penetrated by a miracidium, producing a sporocyst.
Cercariae typically find a snail host through chemotaxis.
The first larval stage is the miracidium, and are found to be attracted to macrocmolecular glycoconjugates associated with a possible snail host.
Cercariae emerge daily from the snail host in a circadian rhythm, dependent on ambient temperature and light.
The snail host(s) are not yet known.
They will die in several hours if they cannot find the snail host.
However, G. truncatula was repeatedly confirmed as the only snail host of F. magna.
The species also serve as a snail host for Fascioloides magna.
The sporocysts then mature into cercariae inside the snail host and are ready to leave.
On hatching, miracidia have 24 hours in which a find a suitable snail host.