13 Tiny Black Bugs In The Basement (With Pictures)

Your basement can be the source of infestation of many bugs and pests in your home.

And when their numbers in the basement increase, the pests spill over to your home. 

In this guide, you’ll find 13 tiny black bugs in the basement that can cause a serious infestation in your home. 

You’ll find out how these bugs enter your basement and what you can do to get rid of these tiny basement bugs. 

Plus, there are hacks and tips to prevent bugs from sneaking into your basement. 

Keep reading.

What Causes Bug Infestation In The Basement?

Clutter, dampness, dirt, and darkness inside the basement are four primary reasons that draw bugs to your basement. 

The cracks, gaps, and voids on the basement floor and walls become their hiding places. 

High dampness in the basement can cause molds on hard surfaces, like the floor, walls, and furniture. 

These molds become the food for many tiny basement bugs. 

And when you don’t clean your basement or don’t remove the clutter, it becomes a haven for the many bugs. 

Another significant factor in attracting bugs to your basement is that it’s cooler than the outdoors during the peak summer months. 

When the outdoors becomes too hot and the moisture sources dry, many bugs look for a damper and temperate place to hide. 

That’s when your basement provides them with the necessary shelter that the bugs desperately want. 

So, what are the little black bugs in the basement that take refuge in your basement? Let’s find it out.

13 Little Black Bugs In The Basement

  1. Drain flies
  2. Mosquitoes
  3. Woodlice
  4. Ground beetles
  5. Carpet beetles
  6. Silverfish
  7. Field crickets
  8. Earwigs
  9. Cockroaches
  10. Spiders
  11. Ants
  12. Booklice
  13. Mold mites

Let’s find out how and why they infest basements. Later in the post, you’ll also find how to prevent and remove these tiny black basement bugs. 

Drain Flies

Tiny black flying bugs in the basement - drain flies

Drain flies in the basement are common because of the high dampness in the basement. 

The most common nesting places of drain flies in the basement are the sump pits, and the basement sink drains.

The idea of drain flies hiding and breeding in the sump pits might not come to your mind.

But the sump pit can be the source of drain flies in the basement. 

Most of the sump pits inside the basement are fully enclosed. And it hides thousands of drain flies that nest and hide there.

When a broken sump pump or the sump pump doesn’t trigger often, the drain flies come out of the sump pits and take over the entire basement. 

There’s also a spillover of drain flies from the sump pits to other areas of your home. 

The waste choking the basement sink drain is also an egg-laying ground for the drain flies. 

The drain flies will lay their eggs on the gunk and wastes choking the basement sink drain. 

When the eggs hatch, the drain fly larvae feed on these wastes. 

The larvae mature into adult drain flies within a couple of weeks and come out of the sink drain holes.

Drain flies are tiny black or gray moth-like flies with short flight spans. 

And when they fly, it looks like they jump and hop.


What Are These Tiny Mosquitoes

You’re no stranger to a swarm of mosquitoes attacking you when you enter your basement. 

These mosquitoes are living and hiding in your basement. And their source is the same as the source of drain flies in the basement. 

Also, the clutter in the basement makes matters worse. Clutter always aids in the spread of mosquitoes in the basement, especially when the area is damp. 

Mosquitoes in the basement lay their eggs on the sump pump’s reservoir. Sump pumps always hold a small amount of water even if they work perfectly well.

And the stagnant water in the sump pump becomes the egg-laying place for mosquitoes in the basement. 

The openings on the sump pump create an easy access point for the mosquitoes to enter the pump and lay their eggs.

However, there’s a catch. 

The presence of mosquitoes in the basement is a spillover of mosquitoes from other areas of your home.

Those other areas can be your yard or swimming pool


Woodlice In Basement

Woodlice, also known as sow bugs or pill bugs, are tiny slow-moving black bugs with scales on their bodies.

These are crustaceans, belonging to the family of crabs and lobsters.

You’ll find them crawling on the basement floor or hiding in the clutter.

These outdoor bugs live underneath wood piles, leaf litter, and rocks.

But woodlice sneak inside the basement through the poorly sealed basement doors and vents when the outdoor temperature increases.

So, their sightings in the basement are common during the summer.

A woodlouse feeds on the molds on the basement’s walls and floor. It can also consume dead insects in the basement. 

The presence of woodlice in the basement is a clear sign of a dampness problem. 

Leaky pipes and sump pumps in the basement increase the dampness levels of the basement, which attracts many bugs.

Woodlice don’t bite. And they’re harmless to humans and pets. 

But not removing woodlice from the basement can make them breed and lay eggs. That can lead to an infestation. 

Ground Beetles

Ground Beetle

Ground beetles enter the basement for the same reasons that the woodlice do. 

Rising temperatures in the summer and the loss of moisture sources make the ground beetles move inside the basement. 

Ground beetles will use any tiny openings in walls and doors to get inside the basement. They can also get inside the house during the summer months. 

The gaps in the walls, floor, and wall voids are their primary hiding places. 

However, they can also hide in the clutter of the basement. 

The presence of other bugs in the basement makes it easy for ground beetles to survive. 

Ground beetles will hunt bugs like silverfish and ants in the basement. 

But ground beetles can’t lay eggs inside the house or basement. It’s because they need the soil to lay their eggs. 

So, ground beetles will not cause any infestation inside the basement. 

Carpet Beetles

Tiny black beetles in the house - black carpet beetles

Adult carpet beetles fly inside human homes during the spring and summer and lay their eggs on natural fabric like wool, leather, fur, feather, and silk. 

They can also lay their eggs in the stored food in your kitchen pantry.

The carpet beetle larvae are damaging pests that feed on the natural fibers and stored food like grains, flour, cereals, and even pet food.

The larvae are a threat to wool and silk rugs and carpets.

As they can infest stored food, the carpet beetle larvae are also pantry pests, on top of being fabric pests. 

However, carpet beetles can fly inside your basement to lay their eggs. 

The adult carpet beetle, a black bug with an oval body like the bed bugs, will lay their eggs on the dead insects in the basement wall and floor voids. 

The carpet beetle larvae, which look like a tiny black worms with brown patches and hairy bristles, feed on the dead insects.

The larvae will mature into adults and breed and lay eggs in the basement. 

That can cause them to spread in the rest of your house. 


Silverfish in sandbox

Another tiny crawling bug that sneaks into the basement is the silverfish.

Silverfish look like small shrimps. They’ve got a tear-shaped body, with three appendages at its rear.

On their head, there’s a pair of antennae.

From a distance, they might look black. But if you observe the silverfish closely, silverfish are either silver or brownish-black with scales on their body.

So, why do silverfish get inside the basement?

They’re one of the bugs with multiple legs that sneak inside basements in the summer months.

Silverfish are moisture-seeking bugs.

When the weather outdoors becomes hot and dry, silverfish look for damp places to live.

That’s the time when they get inside homes through the gaps and cracks on walls, window frames, and door frames.

Places like the bathroom, basement, kitchen, and laundry room are silverfish’s go-to areas inside your home.

It’s because these places are not scorching hot during the summer months and there’s high usage of water in these areas too.

Inside the basement, silverfish will feed on paper, cardboard boxes, and pieces of clothing.

Silverfish survive on carbohydrates and cellulose, which paper and fabric provide.

Field Crickets

Crickets in basement

Field crickets are tiny black shiny crickets that jump. These bugs are moisture chasers. 

And they’ll get inside the basement looking for dampness and darkness.

Your basement is a perfect place for them to hide. The basement’s clutter and the dampness and darkness provide them with a perfect hiding place. 

They’ll feed on dead insects, molds, and things like discarded fabric, paper, and cardboard boxes in the basement. 

It’s not only in summer that crickets can enter homes and basements. The cold in the winter can also make the crickets sneak inside the basement.

These bugs like the warmth of human homes, which is critical for survival. 

Like all cricket species, field crickets are also nocturnal. They’ll remain hidden during the day and come out at night. 


Earwig In Garden

Earwigs are dark brown bugs with pinchers in their abdomen that enter basements when outdoor weather becomes too hot and dry. 

They use the gaps in the basement doors and walls to crawl inside the home and basement. 

Also known as the pincher bugs, earwigs look menacing. 

However, earwigs are harmless. And they don’t bite unless handled. 

Earwigs will hunt the insects living in your basement. And they’ll hide in the gaps and cracks in the basement’s walls, furniture, and floor. 

The clutter in the basement is also their hiding place where they can lurk for their prey. 

Earwigs do not reproduce indoors. They’ll not lay eggs in the basement. So, there’s no way that they’ll cause an infestation. 

However, multiple earwigs can be inside the basement if it’s easy for them to sneak inside. 


Tiny black bugs in the basement oriental cockroach

Dampness and clutter in the basement will attract cockroaches. 

The two most common species of roaches that can hide in the basement are the oriental roach and the big American brown cockroach. 

Oriental roaches love damp and moist places. They’ll feed on all kinds of wet filth and dead insects.

Water leakages, clutter, dirt, stink, and dampness, make the basement an ideal dwelling place for Oriental cockroaches.

Oriental cockroaches are black and smaller than American roaches.

You’ll find oriental cockroaches near water leakages, drains, and on the walls in the basement.

Feeding on wet waste makes the oriental roaches’ poop semi-liquid.

That’s why you might observe smear marks, which are roach feces, on the basement floors and walls.

These roaches also nest and hide in the drains or the sump pits because they prefer to be close to wet places.


Black widow spider hiding

Spiders love clutter and dark areas of your home. And your basement is heaven for them. 

Your basement can be a refuge for many types of spiders. And that includes the two most venomous spiders – the brown recluse and the black widow.

The brown recluse spiders and the black widow spiders will hide in the clutter and wall voids of the basement and in places like garages and attic.

If there are cardboard boxes, it’s even better. Spiders love to hide in cardboard boxes.

Your basement can house multiple spiders of the same species. 

So, for example, if there’s one brown recluse spider in your basement, then chances are there can be multiple brown recluses inside. 

Add bugs and flies to the basement, and it makes your basement a perfect feeding and hunting ground for them. 

Spiders are predators. And the more the bugs are in your basement, the better for spiders.

And bugs in the basement will attract more spiders. 


How Ants Get Inside Kitchen And Home

Many tiny black ant species can sneak inside basements. Pavement ants, sugar ants, odorous ants, and big black carpenter ants can take refuge in your basement. 

Ants enter basements through the gaps in crawl spaces, cracks in the walls, voids, and tiny holes around the wire pathways. 

Dampness in the basement, clutter, rotting wood pieces, and the presence of other bugs make your basement an ideal place for these ants.

However, when ants invade homes, their primary target is your kitchen because your kitchen provides them with the dampness and the food they need to thrive.

Ants in the basement will build their nests in the gaps in the walls and floor. And they’ll feed on the other dead insects in the basement. 

The carpenter ants will target the damp wood pieces in the basement to build their nests. But cracks on the walls are also ideal nesting places for the ants. 

Ant infestation in the basement can quickly skyrocket, and they can spill over inside your home. 

And you don’t notice ants in the basement because you don’t visit your basement often!

So, over time, their numbers in the basement increase, spreading to the rest of the areas of your house. 


Booklice looks like baby roaches

Booklice are tiny moisture bugs that feed on the molds that form on hard surfaces. 

Booklice look like bed bugs because of their oval shape and brownish color. However, they can also look black. 

But booklice aren’t as big as bed bugs. Booklice grow only up to 5-10 mm in size.

Booklice enter homes and basements, looking for dampness when outdoor weather becomes too hot or dry. 

These bugs are harmless, and they don’t bite or draw blood. 

Your damp and moldy basement become a perfect place for the booklice to hide. And if you don’t get rid of them, their numbers skyrocket fast. 

An increase in the number of booklice inside the basement is a piece of great news for spiders and ants. It’s because booklice are easy prey for them.

The bugs in the basement that eat booklice will thrive in their presence, and more bugs will move into your basement. 

Mold Mites

There must be mold mites in the basement if there are molds in the basement. And the worst part is mold mites are microscopic bugs, so it’s impossible to spot them with the naked eye. 

However, when their numbers increase, mold mites look like a layer of gray dust on the moldy surface. 

Excessive moisture in the basement will cause the formation of molds in the basement walls and floor. 

And that will lead to mold mites in the basement. 

Mold mites are harmless bugs. But their presence can cause allergic reactions. 

How To Get Rid Of Bugs In The Basement

  1. Control the moisture in the basement
  2. Clean the basement sink drains
  3. Clean the basement and reduce clutter
  4. Install a dehumidifier
  5. Seal the gaps and cracks in the basement walls and floors
  6. Use a door strip to cover the gap between the basement door and the floor
  7. Use screens on the basement vents
  8. Keep sticky traps
  9. Use insecticide sprays

The above nine steps will remove basement bugs of all shapes and sizes. And they’re the best ways to bug-proof your basement. 

Moisture is one of the biggest reasons that tiny black basement bugs and flies enter your basement. And it can also lead to subterranean termites attacking your basement. 

So, it’s vital to control the moisture and dampness in the basement. 

To do that, fix any water leakages on the basement sinks, faucets, and on sump pump. Ensure that the sump pump is working properly and it’s not leaking.

Clean the basement sink drain to ensure no gunk is blocking the drain. The damp gunk is a feeding and nesting ground for flies like drain flies and mosquitoes. 

The water leakages increase the dampness of the basement floors and walls, making them more attractive to bugs.

Also, install a dehumidifier to reduce the moisture levels in the air. 

Dehumidifiers don’t kill bugs. Removing the dampness in the room’s atmosphere makes your room unattractive to bugs. 

Dehumidifiers are very helpful in preventing tiny allergy-causing mites like dust mites and mold mites.

Follow it up by cleaning the basement and removing the clutter by disposing of unnecessary items. 

Spiders, crickets, earwigs, and many other basement bugs hide in the clutter. 

Get rid of cardboard boxes, wood blocks, and paper piles too. These are the favorite hiding places for spiders. 

Seal the gaps and cracks in the walls. These crevices are hiding places for many tiny basement bugs. 

The dead bugs in the floor and wall voids are the egg-laying grounds for bugs like carpet beetles. And those dead bugs are also food for many basement bugs. 

Repair damaged walls and floors

Use a door strip to cover the gap between the basement door and the floor. The gap is an easy entry point for many bugs.

Also, use window screens with fine mesh on any large vents in the basement to prevent bugs and flies from entering through the ventilation.

Use insecticide sprays or natural bug killers like diatomaceous earth in your basement. You can also keep sticky bug traps to entrap bugs like spiders, roaches, and earwigs hiding in your basement. 

You can also use peppermint oil spray in your basement. The smell of peppermint repels many bugs, including spiders and roaches. 

The strong smell of peppermint also prevents mice and rats from entering your basement because they hate the minty smell too.


The 13 tiny black bugs in the basement are –

  1. Drain flies
  2. Mosquitoes
  3. Woodlice
  4. Ground beetles
  5. Carpet beetles
  6. Silverfish
  7. Earwigs
  8. Crickets
  9. Cockroaches
  10. Spiders
  11. Ants
  12. Booklice
  13. Mold mites

However, other bugs like house centipedes and millipedes can also hide in the basement. 

This guide has nine steps that you can use right now to eliminate the tiny basement bugs and to ensure that no bugs enter your basement. 

However, if the bug infestation is severe in your basement, then you must hire professional pest control to get rid of these bugs.

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