The Spiny Backed Orb Weaver Spider

Spiny Backed Orb Weaver Spider

Spiny Backed Orb Weaver Spider. By Vengolis – Own work, CC BY-SA 4.0

Gasteracantha, commonly known as the Spiny backed orb weaver spider, is a genus of spiders. These spiders can be easily distinguished from others because of their colorful appearance. They are usually harmless to humans but can cause a nuisance by weaving webs around places in our home.


These spiders have spines protruding from their abdomens and have a crab-like shell. The females have white abdomens with black spots and big red spines. The males can have a gray abdomen with white spots and lack the big spines, and are also smaller in size.

Appearance, Behavior, Signs

These spiders are very colorful in appearance. They have white abdomens with black spots and red spines protruding from the edge of their black legs. Their usual size can range from ¼ to ½ inch. Some species might have yellowish abdomens with white spots and black spines.

These pests are usually harmless to humans but can create large webs and multiply quickly. They feed on some insects that can cause damage to crops so these spiders are generally considered to be useful.

Spiny backed orb weaver spiders are mainly found in the edges of woodlands, or gardens. They frequently weave their webs on the edges of gardens, window corners, door corners or porches.

The frequent appearance of these spiders, their webs, and egg sacs can be the most common sign that your place has been infested with the pests.


These species do not enter homes intentionally but can come inside your home unintentionally through potted plants or outside items. And like other pests, they can visit you from window gaps or torn screens. Huge tree limbs that touch the windows can also provide a way to these spiders to enter your house.


Although the spiny orb weavers eat up the mosquitoes of your house, they can actually sometimes become more irritating than them. They can build their webs around places in your home and running into those webs can be very annoying. Therefore, following are some of the ways to get rid of the spiny orb weaver spider:

  • Keep their food source away. They eat insects like moths and mosquitoes that get trapped inside their webs. Reducing the population of these insects would make the spiders go away on their own since they wouldn’t find any food.
  • Destroy their webs with a broom and take the spiders trapped in the broom away from your home and shed them. If you have to kill them, crush them quickly, or let them run down the street.
  • A lemon pledge that you use for dusting can also make these spiders leave the place. Spray some lemon pledge over their webs or any other place they seem to be accumulated in.
  • Alternatively, you can buy a spider spray from a local store and spray it over their webs. But this serves as only a temporary solution and the spiders might come back when the effect of spray is gone.

Spiny Backed Orb Weaver Spider Facts

  • Spiders are not insects, but arachnids.
  • Spiders have 8 legs, while insects have 6.
  • These spiders use their webs to capture their prey insects.