Once inside of the snail body, the miracidium hatches from the egg, and parasitically grows inside of the snail.
12.
A trematode infects a snail with a miracidium larva that either swims to infect the snail, or hatches after the snail ingests the trematode egg.
13.
After post-ingestion hatching or penetration of the snail, the miracidium metamorphoses into a simple, sac-like " mother sporocyst ".
14.
The larvae ( or miracidium ) drill through the wall of the gut and settle in its digestive tract, where they develop into a juvenile stage.
15.
Embryonated eggs are passed into an aquatic environment ( fresh or brackish water ) each containing a fully developed larva, called a " miracidium ".
16.
Alternatively, eggs may hatch in water to release an actively swimming, ciliated larva, the miracidium, which must locate and penetrate the body wall of the snail host.
17.
The water snail is the first intermediate host in which a miracidium ( an embryonated egg discharged in stool ) goes through its developmental stages ( sporocyst, rediae and cercariae ).
18.
This aids the " Clonorchis " in reproduction, because it enables the miracidium to capitalize on one chance occasion of passively being eaten by a snail before the egg dies.
19.
One month-or more with cooler ambient temperatures-after a miracidium has penetrated into the snail, hundreds to thousands of cercariae of the same sex begin to be released through special areas of the sporocyst wall.
20.
The eggs hatch into a miracidium stage, which develops into multiple brooding " L . saxatilis " generally move only to avoid being left above water by the tide while non-brooding ( including castrated ) periwinkles are more active.
