Alright, these wasn't on my bingo list but I'm not so surprised. Nosema is known case in leeches. I wonder if those can do xenoma as well when case is developed to the extreme.

In warm regions I have my own bet, Platydemus manokwari had certain not very picky nematode species . I will wait in this case because depicted flatworm is invasive in colder European regions and not in endemic region of my nematode tip

If you wonder about those white dots here is close up. Those are ciliates from Urceolaria mitra complex. No Trichodina denticles in adhesive disc are present, there is denticulate ring instead of denticles. Diff-Quick, 40x objective.

Isn't it spoon worm proboscis [ Ikedidae family] ? I meeting those on iNat, often misidentified for nemerteans.