Although I have never seen a really big Cutthroat that spotting pattern looks awfully Rainbow to me.

Having said that, I was at a meeting of bios once and somebody ran a series of slides for us to ID. Every fish that looked like a Coastal Cutt was a genetic rainbow and every one that looked like a rainbow was a genetic Cutthroat. So, I know looks can be deceiving.

I mean, some politicians look human........