It might be a horse-fly. It can be dangerous but i don't think it'll hurt your cats. Just in case try to keep your cats away from it. Oh and instead of swatting it, vacuum it up! That's what i do when i'm afraid to swat it or i can't swat it. It works, trust me. Hope it helps and good luck with it! :)

There's a type of fly in my house that I've never seen before. It looks like a normal black house fly but it has what looks like a thick stinger arching downward. It looks like it COULD have a circle on its back but it's really hard to focus on it long enough to make sure.

I'm just a bit confused as to what it is, and am curious if it's dangerous to us or our cats in some way. (We're having a difficult time catching/swatting it.) I live in South Eastern Michigan in the USA, not far from a lake. We often get infestations of Mayflies because of that.

Any ideas? Thanks.