Amphipod?

Found at lembeh, size about 5mm.

Or isopod?

Isopod, as all the visible legs have the same shape. But that's a strange head. Do you have images of it from other angles?

Side profile.

Nice! I'm going to send the photos to my supervisor, Regina Wetzer, who's an isopod specialist. Let's see if she can tell us anything more from the photos.

and by the way ...

the photos, especially the first, are fantastic!

Bart