Miracidia, the ciliated larvae of Digenea, are mostly known as active swimmers that search for the molluscan host and infect it. But many miracidia reach their host “passively”—staying inside the eggs that get eaten by the snail. This strategy is found in most major digenean lineages, and still its understanding is very limited. One of the reasons is that “passive” miracidia can be as small as 20 μm, and secured within a shell that is non-permeable for standard TEM chemicals. Here we continue the series of studies that rely on cryofixation to unfold the structure of these extraordinary organisms. We have for the first time described the fellodistomid miracidium and compared it to the objects of our earlier research—miracidia from families Gymnophallidae and Bucephalidae. These three families likely form a single clade, which adds evolutionary zest to the comparison. The three miracidia are different, but at the same time each pair has at least some features in common. We trace all the functional elements of miracidia (“epithelium”, hypoderm, penetration apparatus, muscles, nerves, excretory system and germinal material) to outline the trends.