Ok, a friend of mine purchased a black moor from my place of work when it was about 1.5". Very black, very obvious telescope eyes. About six months later she asked me about returning it along with one other goldfish because her husband wanted to put something else in her tank, she'd warned me the moor had changed colors. When she brought the fish in I was shocked....he'd turned bright gold and had a very obvious ryukin body shape (he was about 6" long at the time). Now, I've spent many years learning everything I can about tropical fish and only caught the goldfish bug a couple of years ago so I admit there is still a LOT that I haven't seen so this may be a very stupid question, but is there such a thing as a ryukin/moor hybrid? Seems like they should be able to breed, but I don't know.

yes they can breed. any fancy can breed with a fancy.
Your friends old fish is a 'demekin', which is similar to a telescope/ryukin cross.

Thanks! Are there names for any other fancy crosses? I get people coming in all the time with just about any question imaginable and would like to be able to tell them about these interesting hybrids.

All goldfish, Single tail, fantail, telescope, bubble eye, etc. are all the same speices "Carassius Auratus". Since all goldfish are the same speices they can all interbreed with each other and create different varities but none are hybrids. However if you cross a goldfish with a koi then you would have a hybrid because koi and goldfish are different speices. Hybrid fry are also sterile and can't breed.

Here is a link to the different types of goldfish

click here

Thanks peaches, that's what I was looking for

Think of it like dogs. There are many different BREEDS of dogs, but they are all the same species and can breed together.

hehehe....our suppliers are selling us a bunch of mutts! It's kind of like those "designer breeds" like labradoodles and snoodles and such; we just got another one that looks like it could be a demekin in the last order. Now I'll have to tell anyone that asks that I keep mutt fish

Nothing wrong with mutts. We had a dog who was a Springer Spaniel, Irish Setter, and Golden Retriever cross. Our cat was a freebie at a craft show, so we have no clue what her breeding is. She's just a "barn bred" cat.

And when you think about it, aren't just about all goldfish cross-breeds to begin with?

Quite true, same with dogs....someone just decided they should try to get them to look just so and breed anything to get them that way. Mutts are awesome, one of my dogs had a purebred mother but that's as close as I've ever gotten to a purebred , he has all the instincts of a hound, but holds up to cold better than a pure.

Even with plants you see the same selection process. Who knew mustard plants could turn into something like cauliflower, right?