[Developmental cycle of Stomylotrema vicarium]

With metacercariae encysted naturally in the visceral cavity of Megadytes glauca-larvae (Dityscidae), day old unfed chicken and a Belonopterus cayennensis were infected and adults of Stomylotrema vicarium Braun, 1901 obtained. Metacercariae and adults have an excretory bladder with lateral ramifications and 4 groups of 10, exceptionally 12 flame cells on each body side. Very young metacercariae without cysts presented a big stylet. A corresponding virgula-cercaria in Ampullaria canaliculata is supposed.