After so many years... still no ID

[I-NSC]

It is not a nudibranch as it does not have any gills or rhinophores nor is it an underwater banana. It does crawl and is about 5mm in length. The head is on the left while the body is almost circular instead of flat. What could it be? I have initially asked around and one results I received was a juvenile sea cucumber. Can anyone verify and confirm? Appreciate your viewing and comments.

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[drbill]

My guess would be a juvenile sea cucumber too, but I'm not familiar with the fauna in your part of the world. Where exactly did you see it? If it is a sea cucumber, you should see tiny tube feet that it uses for locomotion and possibly a respiratory/feeding tree if it suspension feeds (not all cukes do, many ingest bottom sediments).