Identifying spiders in your home can be a challenge, especially with spiders that are active hunters. These types of spiders exist in large variety and do not breed well indoors, so it is rare to come across the same spider twice. Web building spiders, however, can breed successfully in homes and are more likely to cause concern for homeowners.

Web building spiders have the ability to create large populations, making spider identification easier. They can also build large webs, making their presence widely known. Two common spiders that infest homes are the yellow sac spider (Cheiracanthium spp.) and the brown recluse spider (Loxosceles reclusa). Both of these spiders are a concern for homeowners because they can cause painful bites; however, some people may not immediately be aware of a brown recluse bite as the pain can take several hours to develop.

From a distance, the brown recluse and yellow sac spider can look similar. Use the spider identification information below and supported images to identify which spider might be infesting your home.

YELLOW SAC SPIDER (CHEIRACANTHIUM SPP.)

  • Size: between 5 and 8 millimeters in length
  • Color: pale yellow
  • Eyes: eight pairs, one pair placed closely together in front, one pair spaced on top, and one pair on right and left side
  • Identifying spider trait: banana-yellow abdomen and the second to last segment of their legs, or tarsi, do not point outward or inward

It was previously believed that a yellow sac spider bite could also cause lesions. There has been little evidence to support this, though the bite of this spider can be painful. These spiders are, however, more aggressive than the brown recluse, and more inclined to bite humans.

BROWN RECLUSE SPIDER (LOXOSCELES RECLUSA)

  • Size: between 6 and 20 millimeters in length
  • Color: bodies are usually monochromatic and be can be various shades of light, medium or dark brown
  • Eyes: six pairs, one pair in front and two pairs on either side
  • Identifying spider trait: typically has prominent, darkly shaded violin shape on topside, with fret of violin pointing toward the rear end and the base of the violin covering the eyes (in some cases the violin may be pale or nonexistent)

Brown recluse spiders can have a harmful bite. Their venom has been known, in some cases, to cause skin lesions. However, this type of spider is not usually aggressive and will rarely bite.

Identifying spiders can be a challenge because there are thousands of spider species that exist. These spider identification facts and images will help you identify two of the most dreaded home invaders. If you have a concern about spiders in your home, call Terminix®. Our service technicians will help you find a way to eliminate both the web that caught your attention, and the spider that spun it.

Spider identification Resources: