Spider Beetle vs Bed Bug: What are the Differences?

Written by Emmanuel Kingsley
Published: June 14, 2022
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The sight of a small bug crawling around your office or home may immediately send you into panic mode since nobody wants an infestation of bed bugs. However, before you panic, note that what you saw may have been a spider beetle. It looks quite like a bed bug, but these insects are different from each other in many obvious and subtle ways. Find all the details below. 

Comparing Spider Beetles and Bed Bugs 

A spider beetle differs from a bed bug in size.
Spider BeetleBed Bugs
Diet Forager. Majorly eats whatever it can find. Feeds on blood. Human blood and other mammals.
Physical Appearance Oval-shaped with a hunch-backed body. Oval-shaped with a flat body.  
Scientific Name The scientific name for spider beetle is Ptininae. The general scientific name for bedbugs is Cimicidae.
Gestation Period It takes 3-4 weeks for eggs to hatch.Gestation period is usually 1-2 weeks. 
HabitatMany species are typically found in North America. Usually lives in food locations like warehouses and pantries. Found worldwide. Typically lives in mattresses, furniture, and bedframes. 
Size An adult spider beetle is 1.5mm to 3.5mm long (0.06 -0.14 inches).An adult bed bug is five to seven millimeters long (0.19-0.27 inches).

Key Differences Between a Spider Beetle and a Bed Bug 

The subtlest difference between a spider beetle and a bed bug is in their shape. While both insects are oval-shaped, the bed bug is flatter than the spider beetle. A good picture that may help you spot this difference is that the bed bug is typically shaped like an apple seed, while the spider beetle looks like it is hunch-backed. 

Other important differences between these two insects are explained below.   

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Spider Beetle vs Bed Bug: Diet 

Types of bed bugs - Cimex hemipterus

Bed bugs feed on blood.

©7th Son Studio/Shutterstock.com

This is the greatest difference between a spider beetle and a bed bug. 

Bed bugs have only one thing on their diet and that is blood. There are over 90 species of bedbugs and all of them feed on blood, however, only three of them take human blood. The others take the blood of other mammals

On the other hand, spider beetles are foragers and will eat any kind of food. Spider beetles’ popular food choices are silk, wheat, rye bread, seeds, ginger, almonds, beans, flour, etc. 

You should note that bed bugs attack humans at night while they sleep. They also inject an anesthetic while they are feeding so people don’t feel the pain of their bite until after they are done feeding.

Spider Beetle vs Bed Bugs: Scientific Family and Name 

The general scientific name for bedbugs is Cimicidae. However, there are two species of bed bugs that are involved in human infestation, namely: Cimex Lectularius and Cimex Hemipterus, which are also called the common bed bug and the tropical bed bug respectively. 

As for spider beetles, they form the subfamily Ptininae, in the family Ptinidae. The subfamily contains about 70 genera and 600 species. 

Spider Beetle vs Bed Bugs: Size 

Bed bugs are longer than spider beetles. An adult bed bug is five to seven millimeters long (0.19-0.27 inches), while an adult spider beetle is 1.5mm to 3.5mm long (0.06 -0.14 inches)

Spider Beetle vs Bed Bugs: Reproduction 

The major difference between spider beetles and bed bugs when it comes to reproduction is the gestation period. The gestation period for bed bugs lasts 1-2 weeks while the gestation period for spider beetles is typically 3-4 weeks. 

Spider Beetle vs Bed Bugs: Habitat 

Spider beetles are quite common in North America.

©Henrik Larsson/Shutterstock.com

Bed bugs can be found anywhere in the world. They live in beds, sofas, fabrics, etc. On the other hand, spider beetles are typically found in North America. They are also found mostly in food-populated environments like pantries, warehouses, etc. 

Similarities between a Spider Beetle and a Bed Bug 

There are some similarities between both insects apart from the fact that they are oval-shaped. These similarities include:

They are nocturnal: Both insects conduct their activities during the night after hiding during the day. Bed bugs wait for darkness and humans to fall asleep before proceeding to feed on their blood, and the spider beetle also hides till the night before finding food to feed on. 

They multiply and infest spaces: If you see one bed bug or a spider beetle, there is a very good chance that you already have a horde in your home, workplace, or store. Both insects multiply quickly and serve as pests in your space. While bed bugs go ahead to feast on people in that space, spider beetles can infest food to the point of rendering it useless.

They don’t carry diseases harmful to humans: The spider beetle and the bed bug may bite, with the bed bug even sucking human blood. However, none of them is dangerous or deadly to humans in terms of venom and diseases.

Treatment: How to Prevent and Deal with Spider Beetles and Bed Bugs  

Bed Bugs 

To deal with bed bugs the first step is to identify them and determine if you have an infestation. You can get a professional to help with that or you could use chemicals that they are attracted to as traps to lure them. Another way to know is after the first few bites on your skin. After spotting them the next step is to clean the area you found them and to treat materials in that area. Common bedbug treatment types include:

  • Heat Treatment
  • Cold Treatment 
  • Chemical Treatment 

For full information on dealing with bed bugs, read our guide on how to get rid of bed bugs

Spider Beetles 

To prevent spider beetles in your home, the following tips will help you.  

  • Regularly vacuum, clean the dishes, and mop.
  • Inspect your kitchen pantries.
  • Close up cracks, wall gaps, and holes in the building. 

If you already have an infestation, chemical treatments from pest control services will help you. 

The photo featured at the top of this post is © Pavel Krasensky/Shutterstock.com

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