How to Identify the Black Widow Spider

The Black Widow Spider, named for its mating behavior, is a venomous species found in various parts of the world. The easiest way to identify a Black Widow is by its shiny black body and the distinctive dark red marking on the abdomen of the female spider. However, the male and juvenile Black Widows are more difficult to identify since they are typically a simple brown color throughout their lives. With a bit of practice, you’ll be able to safely identify the Black Widow and avoid the painful and potentially dangerous effects of a bite.

Look for the distinctive red markings on the female. Female Black Widows are famous for the red mark on their abdomen. This mark may appear as an hourglass shape or two separate triangular shapes resembling an hourglass.

• One variation of the Black Widow has a row of red dots instead of the classic hourglass shape.
• There are many color variations among Black Widows. Occasionally, these marks may appear in brown, yellow, or orange. In some cases, the hourglass shape may be replaced by a triangle or a dot.

Observe the glossy black body with no hair. Female Black Widow spiders have a glossy black body. The black color covers their legs and abdomen, except for the red marking area. Their bodies are smooth and hairless.

Look for the brown and white color in juveniles and males. Male and juvenile Black Widows (both male and female) are smaller, brown in color, with white markings. Their appearance differs from that of the female because they have lighter colors, usually tan, brown, or gray. Unlike the female, they do not have the red hourglass marking. Instead, males and juveniles often display white or yellow stripes on their backs.

• Male Black Widows are smaller than females, often about half their size.
• The abdomen of the male is smaller and more slender.
• Male Black Widows are less dangerous than females because their bite is not venomous.

Check for stiff hairs on the legs. Black Widow spiders have eight legs extending from their thorax. The back legs are covered with stiff hairs, which help the spider spin silk around its prey.

Pay attention to the long legs. The legs of the Black Widow are longer in proportion to their body. The front pair of legs are the longest, with the three pairs of back legs being shorter.

• The female's legs are black, while the male and juvenile Black Widows have brown legs.

Examine the size of the spider. The Black Widow is relatively small. The female measures about 3.8 cm in length, including its legs, with the body itself around 1.3 cm.

• The male is much smaller, measuring about 2 cm including its legs.

Look at the rounded abdomen. The Black Widow has a round, swollen abdomen attached to its thorax, positioned behind its hind legs. The color of its abdomen matches that of its head, with characteristic markings visible in this area.

• The male has a smaller abdomen than the female.

Observe the irregular shape of the web. The web of the Black Widow is typically irregular in shape. The silk threads are slightly thicker and stronger compared to those of other spider species. While the web may look chaotic, it is woven with great precision. The typical diameter of a Black Widow’s web is around 30 cm.

Look for webs in dry, dark areas. If you find a web in a brightly lit area, it likely does not belong to a Black Widow. These spiders prefer dark, hidden, and dry locations.

• Black Widows are also often found near the ground, so webs high up are less likely to belong to them.

Pay attention to upside-down spiders. Black Widow spiders have a unique resting posture when they are in their web. At night, they often hang upside down in their web to ambush prey. During the day, they usually hide in secluded spots.

• If a female Black Widow hangs upside down in her web, you may see the deep red mark on her abdomen.

Be cautious of Black Widows in dark, hidden areas. Black Widows are generally reclusive, preferring dark, quiet places such as corners, basements, storage rooms, attics, and outdoor spaces. You might also find them in wood piles, under rocks, in trash heaps, gardens, or even in shoes left outside.

• When working in areas known to house Black Widows, always take safety precautions and carefully observe before stepping into dark corners or reaching into concealed spaces.

Protect yourself. If you must be in an area known to have Black Widows, wear protective clothing. Use gloves, long pants, long sleeves, and closed-toe shoes to reduce the risk of being bitten by a spider.

• Spray insect repellent on your clothes, such as DEET or Picaridin. These repellents can prevent spiders from coming near you.

Contact a pest control service. If you find a Black Widow in your home, avoid trying to approach, interact with, or kill it yourself to prevent the risk of being bitten. Instead, contact a pest control service. They can plan to safely remove the Black Widow for you.

Treat the bite. A Black Widow spider bite can cause muscle stiffness, nausea, vomiting, breathing problems, sweating, itching, swelling, weakness, and abdominal pain. These symptoms may appear within 8 hours of being bitten.

• Seek medical attention as soon as possible.
• Clean the bite with soap and water, then apply a cold compress. You may take over-the-counter pain relievers like Tylenol. Elevate the bitten limb to reduce swelling.
• If a child is bitten, immediately take them to the emergency room.