It was a little bit more transparent before, the red line on it looks like an open brain(vein or something). It was all flat and smooth. It has 2 little black dot(eye I guess) but no horn like sea slug just flat and smooth.
Btw I lost all the tiny snails in my tank, not the bigger one, saw him yesterday night on Parazoanthus which were closed for 2-3 days now they're fully open.
Alive : Turbo, Trochus, Stomatella, Nassarius
The only big snail I lost was a Strombus aurisdianae, I also lost 2 Nerita, 2 Cypraea and all my euplicas.
Btw I saw on the internet Planoceridae sp. 4 and it looks like it but I can't find that familly on reeflex website.