found this today. Cut it off immediately.
What's the damage to the rest?
Don't mind the clover weeds. I have to get a day where it's less than 95 and handle it.
W J
zucchini fungus
Nothing to worry about. Some fruits always abort for one reason or another. Fungi attack the decaying fruit, but don't bother the growing fruit or plant. It is a good idea to cut it off and remove it.
But watch out for squash borers. I get them just about every year, and the first symptom is fruits that look like this. They are worms that get inside the stem and eat their way out. You can't see them on the plant, because they are busily chomping away inside the stem.
Brenda