Whether it’s a giant Madagascar hissing cockroach at the zoo, or a dark brown, nocturnal garbage eater scurrying around in a basement—we’ve all seen a cockroach. They’ve been around since the Carboniferous period, about 350 million years ago. Currently, there are over 4,500 known species of roach, though scientists think there are many more just waiting to be discovered. They run the gamut in size all the way from the size of a cell phone to the size of a penny. With so much diversity, many people wonder: which are the smallest cockroaches, and what do they look like?
Here, we’ll take a deep dive into the five smallest, and most common, species of cockroach. We’ll learn more about how big they grow, what they look like, and how long they live. Then, since most of these small cockroach species live among humans, we’ll go over what steps you need to take if you find a small roach in your home.
The 5 Smallest Cockroach Species
Cockroaches are one of the most well-known, and most reviled, of all insect species. Only about 30 species are known to cohabitate with humans, but of those species, many carry diseases and spread filth. Adults are typically dark brown to reddish-brown in color, while young roaches (nymphs) are pale white. They have six legs and two long antennae, and they tend to scatter when the lights go on.
If you see a small cockroach, it’s important to note whether it has the dark coloring of an adult or the light coloring of a nymph. The presence of nymphs may indicate that you have a serious problem—a breeding population of roaches. But, if the roach is small and dark-colored, then it’s an adult of one of the small species listed below.
This does not mean, however, that you’re out of the woods. Among the smallest species of cockroach, many of them are also the fastest breeding. And, the more nymphs there are, the faster they mature. No matter the size of the roach, if you suspect an infestation, you may want to call an expert. For now though, let’s take a look at five of the smallest types of roach you may encounter.
Brown-banded Cockroaches (Supella longipalpa)
The brown-banded cockroach is the smallest cockroach species you’ll find in your home. Brown-banded cockroaches are one of the most common roach species in the United States. They can live up to a year, and their eggs take about 70 days to incubate. Their maximum size is only ½ inch.
Unlike other species, brown-banded cockroaches prefer heat above 80 degrees. They also tend to congregate on walls—behind pictures and hung art, as well as around warm electrical appliances. They’re recognizable by their alternating amber and dark brown markings.
German Cockroaches (Blattella germanica)
If you find a roach in your home, there’s a good chance it’s a German cockroach. They’re the most common type of peridomestic roach, and they’re particularly common in multi-unit housing structures. Adults reach ½ inch in length and have light brown coloring with darker brown bands running down their bodies.
German cockroaches may be small, but they’re gregarious; they live in large, social groups and reproduce quickly. They prefer living in or around storage and food preparation areas, but they can also be found near plumbing fixtures. Like many peridomestic roach species, they leave behind stains and foul odors.
Three-lined Cockroach (Luridiblatta trivittata)
Three-lined cockroaches are some of the smallest roach species around. Adults top out at only ¼ inch long, and they have no wings. They’re originally from the Mediterranean, though specimens can now be found in diverse parts of the world. While three-lined cockroaches are smaller than German and American cockroaches, they aren’t known for being peridomestic. Instead, they prefer to live outdoors.
They’re lighter in color than other cockroaches too. Three-lined cockroaches are light brown (so light they’re almost translucent) with three black stripes running from head to tail.
Field Cockroach (Blattella vaga)
These roaches prefer to live outside in piles of detritus like dead leaves or mulch. They grow to only ½ inch long and reach full maturity in about three months. Females carry their egg cases with them until the eggs are ready to hatch; each egg case has between 30-40 young in it. Field cockroaches are light brown with darker stripes on the backs of their heads.
Pennsylvania Wood Cockroach (Parcoblatta pennsylvanica)
Pennsylvania wood cockroaches, or, more simply—wood roaches, usually live outside. They can be found in forested areas, and sometimes make their way into homes on firewood. They can grow up to one inch long, though the females are a bit smaller than the males. Additionally, males are capable of flight, while females have only rudimentary wings.
Male wood roaches are light brown in color, while the females are dark brown. Nymphs, rather than being white like most other roach nymphs, are medium brown in color and have no wings.
How to Get Rid of Small Cockroaches
A small roach in your home may be either a nymph of a larger species of roach or an adult of a small species of roach. Either way, small cockroaches may be indicative of an infestation. Professional pest exterminators can diagnose and treat the issue, but homeowners can also often treat infestations with pesticides, traps, and cleanliness.
One of the best things you can do to both keep roaches out of your home, and get rid of them when they’ve taken up residence, is to clean up. Clear all clutter, garbage, and food from the area. Then, set glue traps where you’ve seen the roaches, under sinks, furniture, and at the bases of walls. With care and treatment, most infestations can be managed and eliminated.
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