What is this bug that has a tuft of what looks like light blue fuzz?

Question

It's no bigger than a gnat, and the fuzz trails down from its abdomen.

Answer 1

it might be an aphid that has some toxin leftover or even rarer a deformed aphid. It would be good to kill it because it could spread and take down a tree but I would take a picture of it first cuz you might not ever see another one.

Answer 2

You're absolutely right that it's a species. From the description you gave it's hard to say exactly what, but my first guess is a Wooly Aphid (family: Eriosomatidae) though I can't say what species exactly. If not an aphid it could also be some sort of hopper. I would first check out Wooly Aphids though and see if anything matches what you found.