While flukes may be a fluke, this sample is way too large to be a fluke, plus other anatomical differences exist, the mouth is different. So is the genitalia, which is totally different.
The m bug reproduces in other ways than what a fluke does, parthenogenesis, paedogenisis, then eggs with live young inside and diffusion which comes last.
there is a parent bug to all of this mess, too bad it carries it own set of "invaders". While not a true parasite, it may well be an incidental invader.
On the outside of the larva, molecules of other life forms can be seen, also algae, fungi and arboviruses.