Because Arizona doesn’t contend with extreme cold, many different arachnids that couldn’t survive the harsh winters of the north east can happily live in this warm and dry state. Let’s take a look at the most common spiders in Arizona and whether or not any pose a potential risk to humans.
7 Common Spiders In Arizona
There are a couple of common spiders in Arizona that can cause harm if they bite. Because of this, it is important to learn which spiders pose a risk and which ones only look scary.
1. Black Widow
Scientific Name: Latrodectus
Black widows may be the most well-known venomous spider, though how dangerous its bite is is generally overblown. In most cases, a healthy adult will experience only mild symptoms from a black widow bite with no lasting side effects.
Children, the elderly, and those with compromised immune systems are more likely to have a greater reaction to the bite from a black widow. With that said, however, you should always seek immediate medical attention if you are bitten by a black widow.
Black widows thrive in areas where it is dark and protected. They often make their way indoors and can go unseen in your home until someone bothers their nesting area or unknowingly steps on one.
Black widows are shiny and black, and their bodies measure less than an inch long. They are easy to identify due to their bright red hourglass-shaped markings on their bellies. Female black widows are known to be aggressive and are typically the ones who bite.
2. Wolf Spider
Scientific Name: Lycosidae
Wolf spiders are large and appear deadly, but pose no risk to humans or animals. They can range in size from 1 to 4 inches long, and are often dark in color.
Wolf spiders are not aggressive and won’t bite unless they feel threatened, and even if you do get bitten by one of these arachnids, the worst symptom is typically an itchy bump. One of the most interesting facts about wolf spiders is that they carry all their babies on their backs.
The female wolf spider will lay 100 or more eggs in a protected area. Once the eggs hatch, the babies will climb onto their mother’s back and she will carry them around for several days.
3. Southern House Spider
Scientific Name: Kukulcania hibernalis
Southern house spiders are one of the most common spiders in Arizona. While they do look similar in appearance to other dangerous species, they pose no threat to humans.
They measure no more than an inch long, typically smaller than an inch, and either amber, brown, black, or grey in color. This house spider also has velvet-like light gray hair on its abdomen.
The southern house spider creates flat, tangled webs in homes, barns, and even in bridges. They typically prefer to live indoors where it is protected, but can sometimes be spotted outside under tree bark.
Scientific Name: Theraphosidae
Tarantulas are often the end-all to end-all of spider species in most people’s eyes. They typically think of tarantulas as dangerous, deadly, and downright mean. The truth is, tarantulas pose little risk to humans and no one has ever died from a tarantula bite.
While there are about 30 different tarantula species in Arizona, the western desert tarantula is the species most commonly seen in the state. They are large, growing up to 6 inches in length, and have a brown, black, or tan body.
While they do look rather frightening, the western desert tarantula is not harmful to humans, nor is it aggressive. They typically do not want to live in your home and finding one indoors is not a common sight.
Tarantulas are found in desert areas, as well as grasslands, and live in burrows or dens abandoned by other insects. These large spiders don’t spin webs and instead create underground burrows that they live in.
5. Arizona Brown Spider
Scientific Name: Loxosceles arizonica
The Arizona brown spider is native to Arizona and is related to the brown recluse. While the bites of the Arizona brown spider are still problematic, they don’t pose as much of a risk as the bite of a brown recluse.
The Arizona brown spider prefers to hide in woodpiles and under rocks, and doesn’t generally like to go indoors. Thankfully, they are not aggressive and don’t bite unless they feel threatened.
The body of the Arizona brown spider is brown, of course, and measures about ½ inch with legs that can measure over an inch long. They can be identified by the violin-shaped marking on the top of their head.
6. Grass Spider
Scientific Name: Agelenopsis
Grass spiders, as their name suggests, make their funnel-like webs in grassy areas. It is not uncommon for people to confuse this spider with the wolf spider, though grass spiders are typically thinner, lighter, and have 3 lines on their heads.
These spiders are rather shy and will quickly move away and out of sight if you run across one. Grass spiders are not often seen indoors, but they can be spotted crawling up exterior structures, such as homes and buildings. They are not aggressive and do not pose a threat to humans.
7. Huntsman Spider
Scientific Name: Sparassidae
Huntsman spiders are sometimes referred to as giant crab spiders because of their crab-like appearance. The legs of these large arachnids can measure up to 5 inches long with a body that is a little over ½ an inch.
They are generally found under rocks or loose bark, in rock or log crevices, and simply walking on the ground. They don’t make a web and instead hunt for their prey, which can lead them directly into your home and garage looking for insects to feed on.