I would imagine that there was a single bulb of this variety in with your other ones and after being divided it has finally grown sufficiently large to flower.

That would make sense except that I know this patch intimately for 18 years and there has never been even one. In fact, I have never even seen a daffodil that looks like this one. Have you?

I am wondering if daffodils can spontaneously create a new mutation. Does anyone know? I would love to contact a daffodil breeder but cannot seem to locate one.

There are a lot of similar looking double daffodils. Is it multi headed or have you got several stems in the vase?

It is single headed. There are 5 in this vase. It seems to look similar to a triple I have seen. But why did I get so few flowers this year? There are usually 6-800 in the patch. And can daffodils just spontaously create a new type after many years? It's really strange.

Oh I just had a thought.

Why not post this again but in the hybridizing forum?

The only thing that I can think might have happened is that some seed was produced, it grew on, and eventually the bulbs reached flowering size. BUT, why were the seeds all producing the same kind of flower? Seems too co-incidental.

What I think is more likely is that someone planted those bulbs there.

I think the reason your daffs were not flowering (all the others) was due to their being overcrowded.