Black Widow Spider
Female black widow spiders, the most venomous spider in the United States, have pitch black coloration all over its body, with a very distinctive red hourglass marking on the underside of its abdomen. Female black widows grow around 1/4-inch to 3/4-inch and can be found in human-populated areas, such as garages, woodpiles and even under lawn furniture.
Funnel Web Spider
Funnel Web Spiders have similar physical features to a wolf spider; they have hair all over their body and a smaller abdomen when compared to other spiders; however, funnel spiders are smaller (they grow to about ¼-inch) and prefer to live in the grassy plains. Funnel web spiders are named as such because they build funnel-shaped webs in front of their nests. Their coloration varies from dark brown to black and their venom is not toxic enough to harm humans.
Tarantulas
The most common tarantula living in Arizona is the Arizona blond tarantula. Its name is adapted from the female's coloration, which has a tanned color all over its body; however, the male of species often exhibits a black coloration, mostly along its legs. Male Arizona blond tarantulas have black legs, a red or black abdomen, and a cephalothorax with a deep copper color. Arizona blond tarantulas do not have venom that's toxic enough to kill humans, but they have a painful bite and a set of abdominal hairs that can irritate human skin.
Southern House Spider
Male southern house spiders usually have light to medium brown colors, but females have a dark brown to black coloration. They are commonly found all throughout the southern parts of the US, including Arizona. Female southern house spiders grow around 3/4 --inch and are half as large as the males of the species. Southern house spiders do not have venom strong enough to be dangerous to humans.