What You Need to Know About Noble False Widow Spiders

What You Need to Know About Noble False Widow Spiders
Picture of Israel Alvarez
Israel Alvarez

Owner @ Insight Pest Management

Table of Contents

While Southern California is home to many different spider species, such as the black widow, desert recluse, wolf spiders, and tarantulas, many are not aware of the noble false widow spiders and their unique history here in Southern California. Here we take a closer look at this spider species, how to identify a noble false widow spider, and how they because a member of the California spider fauna.

Key takeaways

  • Learn about the noble false window and how to identify it
  • Understand that the noble false widow is not native to California
  • Learn how dangerous this spider species can be

What are noble false widow spiders?

The noble false widow spider, Steatoda nobilis, is considered to be one of the most invasive species of spiders in the world. This spider species is believed to have originated in and is native to the Canary Islands and Madeira. In the late 1800s, the noble false widow spider hitched a ride in some banana boxes, helping to establish a new home in the United Kingdom before spreading throughout Europe.

Noble false widow spider in Southern California

Here in Southern California, the noble false widow spider is a relatively new resident. In 2011. A group of experts looking for invasive brown widow spiders in Ventura County came across multiple specimens of spiders they were not familiar with. After catching some of these spiders, they returned to the laboratory to begin identification. At this point, they determined that the spiders they had captured were in fact the noble false widow, making this the first discovery of this spider species in the United States, as well as the western hemisphere.

Identifying a noble false widow spider

Because we have many different spider species in Southern California, learning how to identify these different species can be helpful, especially if you have received a bite.

Here we look at everything from their physical appearance to their diet and where you might find the noble false widow spider in or around your home or business.

Physical appearance

The noble false widow has a dark brown front section of the body, with legs that can be similar in dark brown color or more reddish orange in appearance. Their bulbous abdomen is brown in color with cream-colored markings that can resemble the shape of a skull. The females are larger, measuring between 9.5 and 14 mm, with the males slightly smaller, measuring between 7 to 11 mm.

Life cycle

A female noble false widow spider lays eggs, with the average egg sac containing as many as 200 or more eggs. Female spiders can produce multiple egg sacs throughout a single season. Spiderlings emerge from the egg sac 18 days after being laid but will remain in the egg sac until their first molt. At this point, they are able to hunt for their own prey. These spiders can live up to five years.


Noble false widow spiders can be found throughout the year, regardless of climate. In Southern California, you can find these spiders everywhere, both indoors and outdoors. In addition to Ventura County, the noble false widow spiders can also be found in Monterey, San Diego, and Alameda counties and maybe others as they continue to spread.


Noble false widow spiders typically feed on other insects, but they have also been found to eat small reptiles and even bats. They catch their food through predatory behavior, wrapping prey with silk while they bite and inject venom, paralyzing their victims.

Are noble false widow spiders dangerous?

Whether the bite and venom of a noble false widow spider are dangerous or medically significant have been the topic of debate for many years, with some saying that a bite is not much different than a sting from a bee or wasp. However, new research from epidemiologists at NUI Galway published in 2021 shows that the venom transferred through a bite to humans can be medically significant and comparable to the bite of a black widow. Those bitten can experience mild to debilitating pain, intense swelling, changes in blood pressure, nausea, and impaired mobility. In severe cases, necrotizing wounds and bacterial infections can occur, requiring hospitalization. Most of the bites studied occurred when the person was asleep in bed or when the spider was trapped in clothing.

Sharing your space with spiders

While spiders can be very beneficial in the home as they eat and eliminate other pests, having spiders that produce a medically significant bite are not something you want in your home. Sealing entry points and keeping your home free of other insects is one of the best ways to keep spiders from making residence in your home. However, if you see noble false widows in or around your home, it may be time to call professional spider control specialists.

Let the professionals keep you spider-free

Spiders can be beneficial, but when potentially dangerous spiders take up residence in your home, the team at Insight Pest Management is here to help. Our expert technicians will come in a provide a thorough inspection that identifies the presence of noble false widows, as well as any other spiders and pests, eliminate these pests, and help to ensure these pests can no longer access your home. To learn more, schedule a free evaluation today.

Serving all of Ventura County

Locally owned and family operated, we are a top-rated pest and bug control company that uses state-of-the-art equipment to help ensure that pests are located and eliminated. But it doesn’t stop there! Pest prevention is one of the most important parts of pest and bug control. 

Our expert technicians work to ensure that all potential pest entry points are sealed and offer routine treatment options to help ensure your home or business stays protected from future infestations. You don’t have to share your home or business with pests any longer! If you live in the Ventura County area, let the team at Insight Pest Management help you say goodbye to pests once and for all!

Contact us today to schedule a FREE evaluation!

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