- There are 621 species of spiders living in Utah.
- Four types of spiders living in Utah are venomous.
- Black widow spiders live in Utah. Their venomous bite can cause a host of symptoms including pain, fever, nausea, and sweating. While rarely fatal, their bite can prove medically significant in extremely young or immunocompromised persons.
Utah is a state with many nicknames: The Mormon State, Land of the Saints, The Deseret State, and — officially — The Beehive State. Many of these names refer to its Mormon heritage and the industriousness of the state’s people. Aside from its people, the state is also famous for its beautiful natural scenery and vibrant wildlife. Many animals make their home in Utah including the Gila monster and moose. The state is also home to many species of spiders ranging from jumping spiders to orb weavers. Here is a list of 10 spiders in Utah that you can find throughout the state.
#10. Western Spotted Orb Weaver
The western spotted orb weaver, Neoscona oaxacensis, is a member of the orb-weaver family Araneidae. You can find it throughout the western United States, Central and South America, and the Galapagos Islands.
Female western spotted orb weavers range from 9 to 18 millimeters long, while adult males measure 6 to 13 millimeters long. They vary in color but most specimens have a grey or black abdomen covered in cream-colored spots, hence their name. Furthermore, they feature a cream or yellow-colored stripe down the middle of the dorsal side of the abdomen.
Western spotted orb weavers make large, radial-style webs that they use to catch their prey. If you’re looking for these spiders in Utah, you can often find them in orchards, forests, or fields. They pose little threat to humans despite their large size. Bite symptoms typically include only mild pain and swelling.
#9. Utah Crab Spider
Bassaniana utahensis is also known as the Utah crab spider. A member of the crab spider family Thomisidae, you can often find these spiders in Utah. That said, it has also been spotted in Canada and several surrounding states.
Adult females generally measure 6.3 to 8 millimeters and males measure 4.6 to 6 millimeters long. They get their name from not only their distribution but also their crab-like appearance thanks to their long, curved front legs. The carapace, abdomen, and legs look primarily black or light grey with mottled brown and white markings.
Utah crab spiders belong to the bark crab spider genus Bassaniana, and are commonly found in or near trees or other wooden structures. Like other crab spiders, they do not make webs and instead actively hunt for prey. Due to their small size, their bite is not dangerous to humans.
#8. False Black Widow
The false widow spider, Steatoda grossa, belongs to the cobweb spider family Theridiidae. You may also know it by the name the cupboard spider, dark comb-footed spider, or brown house spider. It is widely distributed throughout the world.
Female false black widows measure between 6 and 10.5 millimeters long while males measure slightly smaller. The round, bulbous abdomen usually looks dark purple, brown, or black. You can tell them apart from true black widows because they lack an hourglass-shaped marking on the abdomen.
Like other cobweb spiders, false black widows build irregularly-shaped cobwebs that they use to capture prey. Given their poor eyesight, they rely on sensing vibrations to know when prey enters their webs. They are among the most misunderstood spiders in Utah due to their association with black widows. While not as deadly as true widows, their bite can still cause pain, fever, sweating, and muscle spasms.
#7. Hobo Spider
Most hobo spiders measure between 7 and 14 millimeters long. However, females tend to measure larger than males. They look primarily brown aside from a row of V-shaped markings down the middle of the abdomen. Additionally, they often sport a light stripe in the center of the sternum.
Hobo spiders wait in the back of their funnel-shaped webs for prey to wander inside that they then attack and consume. Due to sensationalized stories, they are one of the more misunderstood spiders in Utah. As their name implies, there is a rumor that they travel by hitching rides in cars and automobiles. Also, many people mistakenly believe hobo spiders are deadly when in reality they pose no danger to humans.
#6. Desert Recluse
The desert recluse, Loxosceles deserta, is a member of the recluse spider family Sicariidae. You can find it throughout the southwestern United States and parts of Mexico.
On average, adult desert recluses measure around 12 millimeters long. That said, they can reach nearly 50 millimeters long with their legs extended. Unlike many spiders, males and females usually measure about the same size. They look mostly tan except for the abdomen which appears light brown. The carapace features a distinctive violin-shaped marking common in many recluse spider species.
Desert recluse spiders do not use webs to capture prey and instead actively hunt for their food. As their name implies, you can often find them in dry, arid regions such as deserts. They are one of the most dangerous spiders in Utah due to their necrotic venom. Common bite symptoms include pain, skin lesions, nausea, vomiting, and fever.
#5. Mouse Spider
Scotophaeus blackwalliis, or the mouse spider, is a member of the ground spider family Gnaphosidae. You can find these spiders in Utah and throughout the western United States as well as Europe.
Adult females can reach nearly 20 to 35 millimeters long while males are smaller. The carapace looks predominantly dark brown and the abdomen appears velvety grey. Due to their appearance and quick, darting movements, people sometimes mistake them for mice, which is where they get their name.
Mouse spiders are active hunters that do make webs. However, they do produce sticky silk that they use to subdue their prey. In addition, they will also readily scavenge for dead insects and other spiders. Some people mistake them for the more deadly mouse spiders in Australia, but they are not closely related. Their bite is not medically significant.
#4. Red-Backed Jumping Spider
The red-backed jumping spider, Phidippus johnsoni, belongs to the jumping spider family Salticidae. It is one of several jumping spiders in Utah, although you can also find it throughout western North America.
Adult red-backed jumping spiders usually measure about 10 millimeters long. That said, males typically measure smaller than females. Like other jumping spiders, they possess bright iridescent chelicerae or mouthparts that usually look bright teal. The abdomen appears bright red, which is where they get their name.
Red-backed jumping spiders hide in retreats during the day and then emerge at night to actively hunt for prey. Instead of using webs, they stalk their prey and then jump from a distance and land a killing blow. Occasionally, females will also cannibalize males before or after mating. They don’t act aggressively by nature and their bite is not medically significant.
#3. Western Black Widow
Latrodectus hesperus is better known as the western black widow. It belongs to the family Theridiidae and is one of the most poisonous spiders in Utah. You can also find it throughout most of western North America, hence its name.
Female western black widows measure between 14 and 16 millimeters long. Meanwhile, males measure about half the size of females. They look almost uniformly glossy black except for a red hourglass-shaped marking on the bottom of the abdomen. While normally red, this marking can sometimes look yellow or even white.
Female western black widows make messy cobwebs that they use to catch their prey. Unlike some other true widows, they do not often cannibalize males. Their venomous bite can cause a host of symptoms including pain, fever, nausea, and sweating. While rarely fatal, their bite can prove medically significant in extremely young or immunocompromised persons.
#2. Bowl and Doily Spider
The bowl and doily spider, Frontinella pyramitela, belongs to the sheet weaver family Linyphiidae. You can find these tiny spiders in Utah as well as throughout much of the United States.
Adult bowl and doily spiders typically measure around 4 millimeters long, with males measuring smaller than females. They look primarily reddish-brown except for their legs which appear yellowish. Furthermore, they feature small white dots along both sides of the abdomen and short hairs all over their body.
As their name implies, bowl and doily spiders make unique webs that they use to catch prey. The web consists of two parts; an inverted dome, or bowl, and a horizontal sheet, or doily. They hang under the bowl and wait for insects to wander into the non-sticky doily below. Their bite is not medically significant due to their small size.
#1. Carolina Wolf Spider
Hogna carolinensis is better known as the Carolina wolf spider. A member of the wolf spider family Lycosidae, it’s one of the largest spiders in Utah and the largest wolf spider in North America.
Adult Carolina wolf spiders can measure up to 50 millimeters long with their legs extended. That said, adult females typically measure from 22 to 35 millimeters long, while males measure 18 to 20 millimeters long. They appear primarily light brown with dark markings on the top of the abdomen. Typically, the bottom of the abdomen and the carapace look darker than the top. Additionally, the males feature orange sides.
Carolina wolf spiders usually ambush prey that wanders past their burrows but can also actively chase down their food. Their venom possesses the unique quality of simultaneously paralyzing and disinfecting their prey. Despite their large size, their bite is not medically significant.
What to Do If a Spider Bites
Most spider bites cause minor injury but you should seek medical care immediately if:
- You were bitten by a dangerous spider such as a black widow or a brown recluse.
- You are unsure whether the bite was from a dangerous spider.
- You have severe pain, abdominal cramping, or a growing wound at the bite site.
- You are having problems breathing or swallowing.
- The area of the sore has to spread redness or red streaks.
If you are sure the spider wasn’t dangerous, you can clean the wound with soap and water and apply an antibiotic ointment three times a day to prevent infection. A cool compress can reduce pain and swelling. If needed, take an over-the-counter pain reliever and use an antihistamine if the wound is itchy.
Summary of 10 Types of Spiders in Utah
Here’s a recap of the 10 spider species found in Utah that we took a look at.
|1||Carolina Wolf Spider||Hogna carolinensis||Females: 22-35 mm; males: 18 to 20 millimeters long.|
|2||Bowl and Doily Spider||Frontinella pyramitela||4 mm; males are smaller than females|
|3||Western Black Widow||Latrodectus hesperus||Females: 14-16 mm; males measure about half the size of females|
|4||Red-Backed Jumping Spider||Phidippus johnsoni||10 mm; males are smaller than females|
|5||Mouse Spider||Scotophaeus blackwalliis||Females: 20-35 mm; males are smaller|
|6||Desert Recluse||Loxosceles deserta||12 mm; can reach nearly 50 mm long with their legs extended|
|7||Hobo Spider||Tegenaria agrestis||7-14 mm; females tend to be larger than males|
|8||False Black Widow||Steatoda grossa||Females: 6-10.5 mm; males are slightly smaller|
|9||Utah Crab Spider||Bassaniana utahensis||Females: 6.3-8 mm; males: 4.6-6 mm|
|10||Western Spotted Orb Weaver||Neoscona oaxacensis||Females: 9-18 mm; males: 6-13 mm|
The photo featured at the top of this post is © SNEHIT PHOTO/Shutterstock.com
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