I've lived in Florida for over 5 years now. While I knew that black widows are native to the state, I had never seen any. Until a few days ago when I saw two in rapid succession. Odd.
One of them was in the swimming pool! Not a friendly guest to swim with. :-/
Fun trivia #1: There are also red and brown widow spiders. They are all found in Florida. (For what it's worth, I did a drawing of a red widow last year.)
Fun trivia #2: While highly venomous, black widow bites are rarely fatal. (Still wouldn't want to test it, though...)