Perhaps you just ate a $1000 Derby Winner Trout with the yellow dot identifying the prize value. Oh boy!Those aren’t the yellow spots on the side you can’t see them in the pic but they looked like a little yellow dot on its belly. Compared to a lot of the other brooders it looked pretty good and it tasted pretty good too.
That is actually a REALLY good thought and makes a lot of sense especially with how most of the stocker trout are crosses between cutties and rainbows. There would be amble opportunity for a mutation like that to happen in the pigment.That is a beast!!! You won't be forgetting the experience anytime soon. Hats off to you buddy!
As for yellow dots on trout bellies, I have caught many trout with those same markings, as I am sure there are a great number of fisherman that can recall seeing those same yellow spots on trout from the past. I cannot add any research data to this, but based on the wide variety of locations I have caught fish with those markings, and basic hereditary science, I would make an educated guess that they are nothing more than birth marks (spots with pigment differences) and are likely the result of either inter-breeding or genetic mutations (sorry if this is getting too deep). There may be some distant relative in the wood pile (Yellowstone cutthroat, German brown, etc.) that had yellowish throat or belly markings and these are just DNA blips showing up many generations down the line. No such thing as "purebred" anything anymore.
Option #2: who knows???
What cannot be denied is the fact that this is one awesome fish!!! Congratulations!