Possible Sea Hare?

[eggplantparrot]

First hitchhiker in a while, closest thing I see on google is this

Video:


It's on a standard size plug for size reference (its tiny), and the thing I poke it with is a #11 hobby blade.

Thanks in advance for ID.

 

[eggplantparrot]

Any takers?

 

[Reefing102]

Just a stab in the dark but looks like a type of flatworm. I don’t think it’s planaria but not entirely sure

 

[WheatToast]

Just a stab in the dark but looks like a type of flatworm. I don’t think it’s planaria but not entirely sure

Personally, like OP, I am leaning more towards some sea slug, given the shape.
Oh mighty @Isopod80, you always seem to have the answers!

 

[minus9]

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