Arizona Bark Scorpion - This scorpion is the most venomous in the United States. Its sting can make humans very ill, and even be fatal in some cases. It can be found in the deserts of Southwest United States, particularly in the Sonoran.
Black Widow Spider - The Black Widow is a very well known spider. The female is famous for the red hourglass shape on the bottom of her abdomen. The western black widow lives in the western United States, and its bite can be considerably toxic to humans.