https://www.ebay.ca/dsc/Collectibles/1/i.html?_ssc=1&_nkw=ashtray+fish

What you are seeing is not where something was attached !! It is a result of the hot metal being poured into the mold and simply bubbling up a bit !! Looks like either brass or bronze !! You can find several forms similar to yours on ebay !! I am just talking about the shape with the open mouth !! Cant see yours up close but it could have come from anywhere !! Japan usually marks their items in some way !! But also could have had a stick on label !!

As close as I could get.

can you take a close up of the part where there may have been something attached ?? Its probably bronze but can`t tell from these pics !! Can just as easily be spelter !!

No, nothing at all. I’m wondering if a part of it is missing. You can tell at the base there is a part that’s shaped a bit differently, as if it attached to maybe an ashtray? I’ve been researching this piece for a long time and nothing comes up.

Certainly looks like a cigar rest !! Is anything written on the bottom of the base ??