Black widow spiders are a fascinating species with some unique features. One particular aspect that often piques people’s interest is the number of eyes they have.
These arachnids are equipped with an impressive set of eight eyes, which are crucial for their survival and ability to catch prey.
The eyes of black widow spiders are arranged in a specific pattern. They have one large pair in the front, which is essential for detecting movements and sensing potential threats or prey.
The other six eyes are arranged in pairs around their head, allowing them to get a broader view of their surroundings, further enhancing their hunting capabilities.
Black Widow Spider Overview
Species and Distribution
The Black Widow Spider, belonging to the Latrodectus genus, is a member of the Family Theridiidae. These spiders are commonly found in:
- Australia
- North America
Physical Characteristics
Black widow spiders exhibit distinct features, such as:
- Shiny, black body
- Red markings (typically hourglass-shaped)
Female black widow spiders usually have a body length of 8 to 13 millimeters and can measure up to 25 to 35 millimeters with their legs extended.
Males, on the other hand, are smaller and exhibit black coloration with white underbellies.
Here is a comparison table of female and male black widow spiders:
Gender | Body Length | Leg Span | Body Color | Underbelly Marking |
---|---|---|---|---|
Female | 8-13 mm | 25-35 mm | Shiny black | Red hourglass |
Male | Smaller | – | Black | White |
Black widow spiders are known for having eight eyes, arranged in two horizontal rows. This vision allows them to efficiently locate and capture their prey.
How Many Eyes Do Black Widow Spiders Have?
Number of Eyes
- Black widow spiders possess a total of eight eyes.
Eyesight Capabilities
- Their eyesight is relatively poor.
- They primarily use their eyes to detect changes in light.
- In contrast, hunting spiders have excellent vision for capturing prey.
Despite having eight eyes, black widow spiders do not rely heavily on their vision. Instead, they typically use other senses such as touch and vibration to navigate their environment and capture prey.
In comparison to hunting spiders, black widows have poor eyesight and mainly use their eyes for detecting changes in light.
Hunting spiders, on the other hand, need excellent vision to hunt and capture prey effectively, as they do not use webs like black widows do 1.
Overall, black widow spiders don’t have good eyesight. Their vision is mostly used for detecting light changes which helps them steer clear of predators, find shelter, and determine their location.
Comparison Table: Black Widow Spiders vs. Hunting Spiders
Feature | Black Widow Spiders | Hunting Spiders |
---|---|---|
Vision | Poor | Excellent |
Prey Capture | Web-based | Active hunting |
Number of Eyes | 8 | 8 (varies) |
Black Widow Spider Varieties
Southern Black Widow
The Southern Black Widow (Latrodectus mactans) is a venomous spider easily identified by its shiny black body and the distinctive red hourglass-shaped mark on its abdomen.
This species is common in the southern parts of the United States.
Characteristics:
- Shiny black body
- Red hourglass-shaped mark
Western Black Widow
The Western Black Widow (Latrodectus hesperus) is predominantly found in the western parts of North America.
They are similar in appearance to the Southern Black Widow but can be distinguished by their slightly more robust body.
Characteristics:
- Larger, more robust body
- Red hourglass-shaped mark
Northern Black Widow
The Northern Black Widow (Latrodectus variolus) is found in the eastern parts of the United States and southern Canada.
Their appearance is similar to other black widows; however, their red markings may be incomplete or broken.
Characteristics:
- Incomplete or broken red markings
- Found in eastern US and southern Canada
Red Widow
The Red Widow (Latrodectus bishopi) is a unique species found only in Florida.
They are named for their reddish-orange body and legs. The red widow lacks the red hourglass-shaped mark present in other widow spiders.
Characteristics:
- Reddish-orange body and legs
- Lacks red hourglass-shaped mark
Brown Widow
The Brown Widow (Latrodectus geometricus) is not as toxic as other widow spiders, but still poses a risk to humans.
They are light brown with an orange hourglass-shaped mark and can be found worldwide.
Characteristics:
- Light brown body
- Orange hourglass-shaped mark
Feature | Southern | Western | Northern | Red | Brown |
---|---|---|---|---|---|
Hourglass Mark Color | Red | Red | Red | Absent | Orange |
Body Color | Black | Black | Black | Red | Brown |
Primary Habitat | Southern US | Western North America | Eastern US and Southern Canada | Florida | Worldwide |
Conclusion
Black widow spiders, with their iconic eight eyes and distinctive markings, are a marvel of nature.
From their unique hunting techniques to their venom’s potency, they’ve earned a reputation in the animal kingdom.
Their presence is not just limited to the wild; they’ve also made a mark in pop culture, inspiring characters like Marvel’s Natasha Romanoff.
Understanding these spiders’ characteristics, behavior, and varieties offers a deeper appreciation for these intriguing arachnids.
Footnotes
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about black widow spiders. Scroll down to have a look at some of them.
Letter 1 – False Widow
Shiny Brown Spider
I often confuse this spider with a black widow because of the silhouette. I’m sure it’s in the Theridiidae family of spiders but I cannot find any solid information. I’m tempted to leave it there because it seems to be a very good hunter of other spiders and it isn’t doing any harm in that little corner of our home.
-John
Location: Kent , Wa . USA
Ed. Note: Before we even had a chance to identify John’s spider he sent us this great link.
Found some information on the curious Spider I sent earlier from this site: http://www.ento.psu.edu/extension/factsheets/Spider/spiders.htm You mention the Steatoda grossa (false black widow) on your site but didn’t include any pictures. I hope you can use the ones I sent. Thanks for your time and your outstanding website
-John
Thanks for doing our work John,
Here is some additional information from Hogue: “The False Widow is very abundant locally and probably suffers considerable undeserved abuse because of its general similarity to the Black Widow, upon which it is reported to prey; it also eats sow bugs.
It lacks the red hourglass mark of the BHlack Widow and has a marbled purplish-brown rather than black abdomen. Females are just over 1/2 inch long. Flase Widows are found in and around houses, under the loose bark of trees, and in rock and wood piles; these spiders are more tolerant of outdoor conditions than are the Black Widows.”
Incidentally, your newly molted female with her cast off skin is a shiny, handsome spider.
Letter 2 – False Widow
False widow – Steatoda – pictures for you…
Dear Bug Man,
I absolutely love your site! In 2005 I was removing some retaining wall blocks in my yard. I lifted one stone and found dozens of these critters scurrying around in the dirt.
Initially I got the heebie jeebies because they looked like black widows. Then I realized we aren’t supposed to have black widows in Puget Sound and that I”ve never seen black widows clustered together like that or living under rocks in the dirt, etc. I figured they must be something else. I went on the web and think I identified it as a false widow.
In fact, it looks like the false widow that you have posted. Can you confirm that this is a false widow? You are free to use the attached pictures if they are better than what you already have.
I killed one so that I could get good enough pictures to ID it. I let the rest scurry off to somewhere safer. Thanks & Best Regards,
Jim Johnston
Everett, WA
Hi Jim,
Thanks for the compliment. We agree that this looks like one of the Cobweb Spiders in the genus Steatoda. Steatoda grossa is sometimes called the False Widow, and your picture is a very close match to one posted on BugGuide also from Washington.
Letter 3 – False Widow
Frightened and curious
Location: Victoria, B.C.
June 23, 2011 10:56 pm
Hey this spider has been living in the corner of our crawlspace for I don’t know how long. I found tons of dead ants and flies around its nest so it had plenty to eat. Also has two egg sacs.
When I initially saw it I thought it was a Black Widow, but it has no hour glass on the bottom and its reddish-brown on the top side. What is this thing? I’m scared to kill it (we are moving and i’m sure the new owners won’t want a huge spider nest in their crawlspace), maybe its a new species, idk.
Signature: Not sure what this means but sign it well!
Dear Not sure …,
This appears to be a False Widow, Steatoda grossa. Though they are not considered to be dangerous, BugGuide does note: “The bite of this spider can produce symptoms that are similar, but much less severe than those of a black widow bite.
In some cases blistering may form at the site of the bite along with physical discomfort that lasts for several days.”
We have also read reports that False Widows prey upon Black Widows, so that may be added incentive to allow them to cohabitate with you.
Letter 4 – False Widow
Subject: False Widow?
Location: San Francisco Bay Area, U.S.
February 22, 2014 10:23 pm
Hello there-
I found this lovely lady (?) up in a corner near the ceiling of our San Francisco garage/basement (we live on a hill, so that wall is actually subterranean). There’s a similar but smaller spider nearby that I can’t get a good picture of because it’s tucked to far into a corner.
I can’t guarantee how true the color are as the pic was taken with a flash. I was initially intrigued by the spider because it looked quite black in the dark and we do get the occasional widow in this region, but now that I’ve seen it up close, I’m wondering if it might be a Steatoda grossa?
Signature: SnorkMaiden
Dear Snorkmaiden,
We agree that your spider looks like the False Widow pictured on BugGuide. Your individual appears to be an immature female, and when she matures, she will lose the markings on the abdomen and BugGuide has nice images of the female life cycle.
Good to know. Many thanks for the response!
Letter 5 – Female Widow Skimmer
Subject: Dragonfly
Location: Gloucester VA
June 26, 2017 12:05 am
A Dragonfly I saw in my yard, pretty big, several inches across, probably about four inches wide. There are so many similar dragonflies that I cannot tell.
Signature: Kitsune
Dear Kitsune,
We have matched your image to an image of a female Widow Skimmer, Libellula luctuosa, on BugGuide. According to BugGuide: “Most commonly found at lakes and ponds, sometimes at streams, and sometimes well away from water.” According to Overton Park Conservancy:
“Finally, the widow skimmer is a dragonfly that sometimes joins the large feeding swarms, but often stops to perch in the grass or on plants rather than flying continuously.
They’re named for the bands of brown-to-black markings on their wings. Males have an extra wing of white coloring outside the black lines. Their graceful flight is very much like a butterfly’s.”
Letter 6 – Immature Black Widow
White spider with hour-glass dots on back
March 15, 2010
Found on a dead rabbit, amid the fluff of it’s shed fur. The rabbit had been under an old tin bucket and when I lifted it up, this spider was on the fur.
Colleen
Albuquerque, NM
Hi Colleen,
This is an immature Black Widow, probably a Western Black Widow, Latrodectus hesperus. The immature spiders often have patterns on the back which become a solid glossy black as the spider matures.
Letter 7 – Immature Black Widow
I’m freaked out. There were two of them.
Location: Souther California
October 27, 2011 9:41 pm
I just moved to L.A. I didn’t have much furniture so I ran to the Goodwill and grabbed a rolling cabinet for the kitchen. That was last week. And today I was greeted by two of these terrifying creatures.
I’ve been searching and searching online and am beginning to get suspicious. Some places say it’s harmless, some say it’s an immature female black widow. What is it?? Can it hurt my cat?
A picture of its top and its bottom.
Signature: Freaking Out
Dear Freaking Out,
This is an immature Black Widow, most likely the Western Black Widow. They are quite common in Southern California. They are not aggressive. They rarely leave their webs.
Letter 8 – Immature Black Widow
Subject: Australian Redback in Louisiana?
Location: Leesville, Louisiana
May 4, 2017 8:35 pm
I’ve found several of these spiders over the last two years. They have red markings on the back unlike black widows that have a red hour glass on the abdomen. I also noticed some white markings as well. Curious if this could be an Australian Redback???
This one was released back to the woods this evening. May the 4th be with him.
Signature: Thanks, Lee
Dear Lee,
This is an immature female Black Widow Spider. When she matures, she will lose the red and black markings on the upper surface of the abdomen. She should still have the red hourglass marking on the ventral surface.
Your confusion regarding the Australian Redback Spider is understandable as they are in the same genus as the Black Widow. P.S. Is your town named for you?
Letter 9 – Immature Black Widow
Subject: spider
Geographic location of the bug: forestville California 95436
Date: 01/01/2019
Time: 01:16 AM EDT
Your letter to the bugman: Found this in my sons sandbox very pretty just wondering what it is.
How you want your letter signed: Hannah
Dear Hannah,
This appears to be an immature, female Black Widow which is pictured on BugGuide. You should use this as an opportunity to teach your son about a species of spider that should be avoided. According to BugGuide:
“Caution: Anyone bitten by a western black widow spider should receive prompt and proper medical treatment. While the black widow is considered the most venomous spider in North America, death from a black widow spider bite is highly unlikely.
For the most part, the black widow’s bite may be felt only as a pin prick, during which the spider’s fangs inject a minute amount of highly toxic venom under the skin. The severity of the victim’s reaction depends on his or her age and health, and on the area of the body that is bitten.
Local swelling and redness at the site may be followed in one to three hours by intense spasmodic pain, which can travel throughout the affected limbs and body, settling in the abdomen and back (intense abdominal cramping, described as similar to appendicitis), and can last 48 hours or longer.
Elderly patients or young children run a higher risk of severe reactions, but it is rare for bites to result in death; only sixty-three having been reported in the United States between 1950 and 1959 (Miller, 1992). Other symptoms can include nausea and profuse perspiration. If left untreated, tremors, convulsions and unconsciousness may result. When death does occur, it is due to suffocation.”
i saw an immature black widow today and it was reflecting silver in the sun when i pulled out an old broom by the door. At first I thought it was a beetle, but when i looked down on it, it looked exactly like your image on the rabbit fur but it was shiny. it was originally behind some plants by my basement door, i guess it hid in the plant during the heat of the day. The rain is bringing all kinds of bugs out of their normally damp and dark but now are wet habitats. Time to spray the door with pine sol. They do not like it when we put it out in basement:)
I am so happy to find out today that there is such a spider as a “false black widow”! I found two of these (I hope) in my home this week here in Castle Rock, WA. I captured them and have them in clear containers and am feeding them live flies and drops of water. They are both still alive after about five days. I have never seen a Black Widow in the state of Washington, do you know if they live here? I am about 100 miles from the Pacific Ocean. Now that I am fairly sure they are not Black Widows I suppose I should set them free but shudder at the thought of running across them while I weed my garden! I am over 70 years old!
The Western Black Widow has been reported from Washington and British Columbia, according to BugGuide.
How fast can a “false black widow” crawl? Mine goes pretty darn fast. How fast does a Black Widow crawl?
Both can scuttle quite quickly.