*Also see our roach control page
The name cockroach derives from the Spanish language cucaracha meaning cockroach. The transition of the word from Spanish to English came from the slang over time from “cuc-a-racha” to “cock-roach”. The scientific name derives from the Latin name for the insect.
There are 4,300 known species of cockroaches worldwide, and more are discovered all the time. Seventy of those species call North America their home. Out of all the species in the world, only around 30 to 35 are considered pests. The total number of roach species almost matches the number of mammal species, which are 5,400. Cockroaches today have related families and species still tied up in identification and yet to be discovered in the dense tropical regions around the world. They are the most successful ancient insect on the planet. These critters will eat anything and can survive absolutely anywhere other than the Polar Regions and above 2,000 meters in elevation. They are known to span and inhabit regions like the tropical rainforests, tropical forests, temperate forests, deserts, grasslands, and salt marshes. The cockroach order Blattodea is amongst some of the most talented and well adapted species of roaches. This family has the qualities of a super insect: some can live without water, can fly, are the fastest insect, are the most ancient, and can survive high levels of radiation and can survive by eating anything including their own vomit and each other.
The cockroach, having been present on the planet amongst the first insects, currently has no proven origin. Scientist know that most roaches have come from the tropical regions all over the world and adapted to colder conditions - having over 300milion years to do so. The roach is suspected to have come onto the scene around 355 million years ago with the earliest roach-like fossil. They call this specimen a roachid, or the blattopteran. The fossil doesn’t exactly mimic todays roach with it being remarkably close to its cousin in evolution, the praying mantis, which does share features in this fossil.
The distribution of cockroaches is worldwide. They have evolved to live alongside humans and they do it well. The cockroach, like most insects, gained passports to any country through the aid of man. During the early centuries through trade routes, the Roach species became an invasive species on every continent humans inhabited. They are more prevalent in the tropical regions, but they can survive anywhere humans have established homes and food sources.
The Cockroach has been on the planet for approximately 250 to 300 million years. This dates back to as early as the Carboniferous times. Theories have speculated that the ancient ancestor of the cockroach predates the dinosaurs. During this insect order’s time on Earth, it has changed very little, keeping its features primitive or ancient like previous generations. It was said that the cockroach was amongst the first great expansion of the insect species.
The roaches appear to have achieved the optimum body form and other key features early in their evolution history. The theory is that the cockroach evolved the feature to fold their wings over their body to allow them the vital protect they needed. The traits gave the roach the ability to hide from predators and to escape various dangers to survive extinction where most insects were not successful.
Scientists also state that the development of the ootheca or egg sac carried by the female cockroach gave critical parental care and protection to sustain numerous generations allowing the species to survive countless millennia. Cockroaches have been clearly traced back to ancestral fossils that have remarkably almost the same morphology as current day roaches. Roaches have the innate ability to adapt to any situational condition that arises.
Another helpful adaptation is that cockroaches harbor a wide variety of symbionts in their gut as well as fat bodies. Scientific theories make the association that the microbes present have played a large role in the adaptation, evolution, and survival of cockroach species. The hindguts of most cockroaches, apart from one family of five species that have been examined, harbor a wide variety of microbes, including ciliates, amoebae, flagellates, and various prokaryotes. These microbial organisms all are believed to play a major role in digestion and the efficiency of the roach.
The term “blatta” is derived from several branches of Greek languages for cockroach. Cockroaches are featured in literature and songs throughout history.
The Cockroach is featured in the "La Cucaracha" meaning "The Cockroach" that is a traditional Spanish folk-corrido or song that became popular in Mexico during the Mexican Revolution. The song is about the concern of a cockroach that has lost one of its six legs and is struggling to walk with the remaining five.
There are many different types of roaches throughout the world, based on the regions they dwell in. Cockroaches can inhabit inside the home, outside the home, or both. If a roach prefers to dwell outside it is called a feral roach. The feral roaches still may end up inside the home but their survival is independent of humans. Next are the peridomestic roaches that can survive inside or outside the home. Then finally, the domestic roaches base their habitats of living inside homes only. These three regions allow you to further understand the cockroach and identify them.
This family of cockroaches is the largest by size and species. Blaberidae cockroaches in some genera can be very large, like the Blaberus which is extremely large and reaches 80mm or longer. There are also over a dozen genera of Blaberid roaches with 2,000 species.
This family is most commonly known as the wood cockroach or wood roach family. This family clings to the subtropical and tropical regions in the world. The Blattellids are known to be small outdoor roaches and wood roaches.
This family is known as the Blattid cockroaches. This is a diverse family with many genera and hundreds of species. The two genera Periplaneta and Blatta are the most widely distributed, whereas the rest of the genera are more regionally adapted. This family of roaches is known for being rather large and tend to prefer living outdoors. The species is commonly called Palmetto bugs.
This small family of roaches is commonly referred to as Sand Cockroaches. There are only a few described genera with around 100 to 150 species. The genera of the Arenivaga have evolved a system of absorbing moisture through the environment. Since most of this family is found in dry desert-like areas, this skill comes in handy.
This is the most primitive or ancient family of cockroaches. This family has one genus and only 10 species or less. They are found in rotten logs in the United States, Korea, China, and Russia. They are reddish brown and both sexes are wingless as adults.
This is one of the temporary genera that have an unknown placement for it amongst the roaches. The Nicticola genus does not contain endosymbiotic bacteria like the rest of its cousins. Many of this species has gone unidentified in this family so the current species count of roaches is much higher due to the undecided nature. The vast majority of cockroach species live in tropical regions of the world. These tropical regions are part of the world that has not been adequately assessed to establish the diversity of insect life.
Through extensive studies and research, the cockroach species have been shown to be extremely closely related to termites. The microbial symbionts in both roaches and termites are actually identical if not for the same purpose. Wood cockroaches are proven to have given rise to the termite family, and are at least the last connection in the lineage between the two forms of cockroach. The termites and wood cockroaches have modified symbionts to digest their wood that they consume. This inspired further research to knowing why. The roaches have obviously been on the planet longer than termite so they must have splintered off at some point countless millennia ago to become this modified roach family. The termite is actually an odd version of the cockroach that is one of the first insects to evolve on the earth!
This connection was made by the symbionts that are found in the gut of the two insects. They’re referred to as endomicrobia. The endomicrobia are classified as cytoplasmic symbiont protozoan in the guts of roaches and termites. Along with a host of bacteria and other flagellates that aid in digestion. Termites may look like white ants, but new genetic research confirms they are really a social kind of cockroach. The fact that normal cockroaches are primarily solitary animals and are compared with the termite’s complex society is an extreme thought. Researchers have also added that both species practice coprophagy, or eating feces. This fact could very well have led termites to evolve in the first place. Scientists had long known that cockroaches and termites were related to each other and to praying mantises. Some of the features they share include specialized cases that enclose their eggs, and perforations in the internal parts of their heads.
The termites over the years, decades, and millennia have been labeled with the name of the white ant. This term until recent years made sense being that the ants are in the social insect order. They live in colonies underground and have social rankings as well as queens. The major differences are the external anatomies and the choice to consume wood. Though there are some ant species that choose to call wood dwellings their home they do not actually ingest the wood. The ants merely reposition the wood or kick it out for the colony to grow within. Sometimes the ants will suck the moisture and oils out of the wood. Wood isn’t the ants’ primary source or choice of nourishment like the termite.
The termite has actually evolved to encase microbes and symbionts in the gut to aid in the digestion of wood. This is also a characteristic of all cockroach families with the exception of one family. In recent studies the push has been made to classify the cockroaches and termites into their own separate order. The research urges that the termites are not social pale ants, but actually social cockroaches.
They have moved the termites into the order Blattodea and the original order of Isoptera is now the infraorder under the cockroach order. The termites are actually stated as a cockroach family by entomologist Paul Eggleton from the natural history museum of London. Dr. Eggleton and his colleagues now conclude that the termites are a species of cockroach. The termite species has just evolved to mimic the social classes of the bees, ants, and wasp order.
Image source: vtaide.com
The image above is a general life cycle of a cockroach.
Once the male and female roach reproduce or copulate the new generation begins brewing. The fertilized female now begins creating an egg capsule. The egg capsule created by the female cockroach is called an ootheca. This egg capsule grows as it fills up with up to sixty or more eggs. The egg swells and bulges out from the abdomen. Each species of roach deals with the ootheca differently. Some carry it until the young hatch, or drop the egg after carrying it for a time period, or finally just drop the ootheca once it is produced.
Once the young or nymph cockroach emerge, they then begin a 9-12 month nymph stage as they molt and grow to reach the adult stage. This phase of the life cycle can encompass as many as six nymph stages. The roach species have been known to in some cases in periods of improper diets to undergo over 10 to 15 nymph stages. The type of development the roaches undergo is called a hemimetabolus or paurometabolous metamorphosis. Hemimetabolus or paurometabolous means development by gradual metamorphosis in nymph stages that resemble small adults. After each molt, the cockroaches are white and the exoskeleton is soft and hardens short after a few hours.
The current cockroach anatomy is split up into three main regions:
The external anatomy is made up of:
Roaches have two forewings and two hind wings. The wings are called the left and right forewings and hind wings. The forewings are sometimes extended to cover the body of the roach. The six legs are named right foreleg, left foreleg, right mid-leg, left mid-leg, right hind-leg, and left hind-leg.
The exoskeleton has a region behind the head that is like a shield called the prothorex or pronotum. The legs are divided up into segments from the body out, coxa, trochanter, femur, tibia, and ending at the tarsus.
Internally, Cockroaches have a vast array of organs including:
*See our step-by-step Roach Identification Guide for complete identification information.
The cockroach has three body segments, six legs, and one pair of antennae. This is the common key morphology of all class Insecta lineages, or orders of insects. The exoskeleton is a hard protective covering and incases the internal organs. The exoskeleton is commonly divided into sclerites or plates. Roaches have unique mouthparts called the labrum, mandible, labium, and maxilla.
The differences between sexes is either clear to distinguish, or the species of roach is dimorphic. Dimorphism means that both sexes are exteriorly identical. In the dimorphic roach species both sexes possess wings and other similar features. Though several species of males have wings in the adult stage and the females remain wingless from the transition from nymph to adult. Then, in some cases, the wing lengths of species and body length sizes are different between sexes.
Do cockroaches bite?
The cockroach can in fact bite humans. All cockroaches have mandibles and a nasty hunger that never ends, making the roach always in search of a food source. Though cockroach bites are rare most bites will occur in extreme cases of high populations or lack of food. In some cases, bites could occur while humans are falling asleep with food residue on clothing or on the face or skin which can draw the roaches in. They can feed on human flesh but the roach would much rather prefer the less luxurious dining style of leftover crumbs and scraps.
If a bite does occur this can be no joking matter. The bite can be almost unnoticeable but can result in a nasty infection or worse. The typical cockroach lifestyle of crawling through and living in the must filthy locations can allow the roaches to harbor a host of bacteria, parasites, viruses, and other microorganisms.
Do cockroaches fly?
Yes - cockroaches have wings that they use to fly. The adult roaches, and more commonly the male roaches, have wings to locate females. The wings allow the roach to travel more easily. Though not all roaches have wings and most of the roaches’ life is spent wingless until it is a mature adult. The nymphs are highly skilled jumpers, climbers, and sprinters. So no matter the stage of life the cockroach is an evasive creature.
What do cockroach droppings look like?
Cockroach droppings, depending on how fresh or not they are, are around one millimeter in diameter or smaller. The feces are also circular or spherical. The round droppings can vary in size depending on the life stage and size of the roach. The colors may vary as well from black, light brown, dark brown or brownish green. The color also depends on the diet of the roach.
What attracts cockroaches?
Research shows that cockroaches are drawn to one another. They pick up the pheromones given off by nearby roaches by the specialize antennae. The roach has over a hundred segments on each antenna that allow it to scene the presence of other roaches. Cockroaches do travel in packs once together. They unknowingly travel as a pack and prefer to be in groups. This factor allows them to protect one another and create new generations.
There are many factors that draw in and attract a host of different roach species. The feral roaches or wood roaches are oddly attracted to spotlights and can be uncontrollably attracted to homes. As a result the feral roaches are sometimes caught in the home.
Then in some cases the semi-domestic and domestic roaches are drawn to the primary source of clutter and food. The peridomestic and domestic roaches need to feed on the food humans eat, the waste, and trash of this food.
What do cockroaches do?
The cockroach loves to forage and eat at all hours. They also love to wonder around discovering new shelters, foods, and water sources. The number one concern of the cockroach is eating and finding water. The cockroaches’ kryptonite, so to speak, is its unavoidable urge to eat. They also love to be touched on all sides so they will hide in any crack and crevice they can fit in. The roaches also like to do most of their foraging in the night hours. They spend over 75 percent of the day resting or hiding.
Do cockroaches and asthma have a correlation?
Yes - cockroaches do cause asthma. The immune system works its best to try to prevent any foreign substance from entering into the body like bacteria and viruses. This response is to save us from a potentially dangerous illness or disease. The allergies come from the immune system overreacting once we inhale, swallow, or touch any foreign substances. These substances are called allergens. This response triggers the cells and body to attempt blocking these foreign particles resulting in the person having allergies.
The cockroach allergen is from the feces, saliva, and bodies of the roaches themselves in the vicinity of the allergy prone person. Over 80 to 90% of the urban homes have cockroaches, and from 900 to 300,000 insects. This overwhelming presence as a result is creating an increased chance of allergies becoming an issue and new ones becoming created.
Source: AAFA or the Asthma and Allergy Foundation of America
Do cockroaches carry disease?
During the average cockroach adventure, they will find many dirty and filthy locations. This lifestyle makes the roach very dangerous. The cockroach can pick up or be introduced to a host of microbes such as bacteria and viruses. One of the cockroach diseases is called cockroach gastroenteritis. This is a bacterial infection the bacteria causes diarrhea and is a medicinal illness categorized by inflammation.
Do cockroaches come out at night?
Cockroaches are nocturnal in small populations. They prefer to hide their presence so to make scavenging missions safer. In larger populations the roaches can be seen during the day. This is usually one of the key signs of a high population, along with a musk or odor.
How far can cockroaches jump?
In recent research it has been recorded that the cockroach can jump over 48 times its body length! In measuring terms this is over 35 centimeters. This skill allows this roaches to jump all over the home at night unnoticed.
What is the average cockroach lifespan?
Cockroaches can live anywhere from six to 24 months depending on the area they inhabit. This fact can be arguable in domestic pet roaches that are in a controlled, safe environment and have constant nourishment resources. In fact, many people all over the world buy cockroaches and raise them as pets! This domestication of the species throws off the expected life span. The difference between a wild roaches’ life span and a domesticated roaches’ life span are very different but typically they both live at the longest two years or less.
Do cockroaches like beer?
Roaches do love beer. Why do you ask? Well they are drawn to the aroma of certain beer hops and brewing styles, along with the sugar in beer which is a natural give away. First you would want to take a jam jar or deep bowl with a rounded inside lip. Coat the inner lip with Vaseline. This is so the roaches won't be able to escape. The next step is to then put a slice of beer-soaked bread at the bottom. The cockroaches will be attracted by the smell of beer, but the Vaseline-coated lip will make it impossible for them to escape. You can then dispose of them however you see fit.
Could cockroaches survive an atomic bomb?
Cockroaches actually couldn’t survive the initial blast or explosion like any other organism. The cockroach is only able to withstand higher levels of radiation. The roach is recorded to be over 15 times more resistant to radiation than humans.
Where are cockroaches commonly found?
Roaches love dark, warm, dirty, and moist locations. They will thrive in these conditions and high populations congregate in these areas with these characteristics. This means that roaches are typically found in places like sewers, dirty homes, and abandon buildings. All of these places are dark, dirty, and full of clutter. Roaches also like to eat other animal feces so they can be drawn to all sources of pets and animals.
What do you call cockroaches that live outside or outdoors?
Outdoor roaches are called feral cockroaches. Feral roaches do not like being indoors, and often are by mistake. They have adapted to be outside so hints the term feral or wild. The wood roach species is a feral roach and has adapted to feed on the organic matter and wood to survive outdoors.
What are the natural predators of cockroaches?
There are a host of amphibians and reptiles that feed on the cockroach species. Small reptiles like geckos, lizards, iguanas, and young snakes. Then amphibians like frogs and toads. There are also a host of insects and arachnids. There are beetles, wasps, and most spiders hunt roaches. Roaches are also attacked by funguses that spread when a roache makes contact with one another.
Best ways to make your home roach proof:
Top three cockroaches that are considered pests in North America
“Amazing Roach Facts.” Discovery Kids. N.p., n.d. Web. 21 Nov. 2013.
Eiseman, Charley, Noah Charney, and John Carlson. Tracks & Sign of Insects & Other Invertebrates: Guide to North American Species. Mechanicsburg, PA: Stackpole, 2010. Print.
Evans, Arthur V. National Wildlife Federation Field Guide to Insects and Spiders & Related Species of North America. New York: Sterling Pub., 2007. Print.
“Integrative and Comparative Biology.” Cockroaches: Ecology, Behavior, and Natural History. William J. Bell, Louis M. Roth, and Christine A. Nalepa. Oxford Journals and The Society for Integrative and Comparative Biology, 19 July 2008. Web. 21 Nov. 2013.
Resh, Vincent H., and Ring T. Cardé. Encyclopedia of Insects. Amsterdam: Academic, 2003. Print.