I have a variety of iris at home and this year three plants have odd
blooms on them I've never seen before. I don't know if they're just
blooming for the first time or if they're defective or virus or the
result of some accidental cross. Both petals and sepals are narrow and
it's bearded.

A photo is at http://www.amherst.edu/~jkprice/yaws/odd-iris.gif

The image is sort of large, but I did want you to be able to see how odd
it is.

Should I just rip it out now so it doesn't spread?

Janet