Cockroach
Cockroaches include about 4,600 described species, yet only about 30 of them have ever settled into human habitats. Those few have given the whole group its reputation as dirty pests. Most of their relatives are small, inoffensive animals scattered across habitats around the world. One study from 2014 suggests that people fear cockroaches more than they fear mosquitoes. This documentary asks how a plain insect with so few special adaptations became so widespread and so hardy. It asks why some cockroaches may be closer kin to termites than to other cockroaches. And it asks what these animals can teach scientists about group decisions, personality and survival.
The Spanish word cucaracha is the ancestor of the English word cockroach. By the 1620s, English speakers had reshaped it through folk etymology into the two parts "cock" and "roach". The scientific name draws on the Latin blatta, meaning an insect that shuns the light. Classical Latin used that word for mantids as well as cockroaches. Today the group is catalogued as Blattodea, with over 460 genera described. The older name Blattaria referred only to true cockroaches, while Blattodea also takes in the termites.
About 320 million years ago, in the Carboniferous period, the first cockroach-like insects appeared in the fossil record. Paleontologists call them roachoids or blattopterans. A long external ovipositor, an egg-laying organ, distinguishes them from modern cockroaches. Roachoids are considered the common ancestor of both mantises and modern cockroaches. Their exact relationship to living roaches is still disputed, because fossils rarely preserve the body, hind wings and mouthparts. The earliest definitive fossils of modern crown group cockroaches belong to the family Corydiidae. They come from Late Jurassic rock in Russia and from the Kimmeridgian-aged Karabastau Formation of Kazakhstan.
A hypothesis from 1934 first tied termites to the wood-eating cockroaches of the genus Cryptocercus. It rested on the similar symbiotic gut flagellates found in both groups. In 1965, F. A. McKittrick added support by noting similar physical traits in some termites and cockroach nymphs. Later genetic work went further. It showed that termites sit deep inside the cockroach family tree, so some cockroach groups are closer to termites than to other cockroaches. That makes Blattaria paraphyletic, meaning it leaves out some descendants of its own ancestor. A cladogram by Inward, Beccaloni and Eggleton in 2007 lays out these relationships. Termites were once treated as a separate order, Isoptera. Some scientists would now reclassify them as a single family, Termitidae. Others prefer an epifamily called Termitoidae, which keeps family-level classification intact.
At 8 cm long and up to 35 g, the Australian giant burrowing cockroach, Macropanesthia rhinoceros, is the world's heaviest. The Central American giant cockroach, Blaberus giganteus, is comparable in size. The longest species is Megaloblatta longipennis, which reaches 97 mm in length and 45 mm across. Another Central and South American species, Megaloblatta blaberoides, has the largest wingspan, up to 185 mm. At the small end, Attaphila cockroaches live with leaf-cutter ants and grow to about 3.5 mm. Most species fall in between, around the size of a thumbnail.
Three thoracic segments and a ten-segmented abdomen make up the body, which is broad and flattened with a relatively small head. Most species are reddish-brown to dark brown. The eyes are large and compound, with two ocelli, and the antennae are long and flexible. Mouthparts on the underside of the head include chewing mandibles, salivary glands and touch and taste receptors. A tough exoskeleton containing calcium carbonate protects the organs and anchors the muscles. Wax coats it to repel water.
The tegmina, the tough first pair of wings, lie like a shield over the membranous hind wings that do the flying. Wings attach to the second and third thoracic segments. Three pairs of sturdy legs, each ending in five claws, attach to the three thoracic segments. The front legs are shortest and the hind legs longest, and the hind pair supplies most of the push when the insect runs. Spines on the legs were once thought to be sensory. Observations of the gait on sand and wire meshes showed that they help on difficult terrain, and engineers have used them as inspiration for robotic legs.
North America has 50 cockroach species in five families, while Australia has 450. The group tolerates a range of climates from Arctic cold to tropical heat, and tropical species are often much larger than temperate ones. Many live in leaf litter, matted vegetation, rotting wood, stump holes, cavities under bark, log piles and debris. Some live in arid regions and survive without access to water sources. Others are aquatic, living near the surface of water bodies, including bromeliad phytotelmata, and diving to forage. Most of these breathe by piercing the surface with the tip of the abdomen, which works as a snorkel. Some carry a bubble of air under the thoracic shield and can stay submerged for up to 40 minutes. In the forest canopy, cockroaches may be one of the main types of invertebrate. They hide by day in crevices, dead leaves, bird and insect nests or among epiphytes, then emerge at night to feed.
German cockroaches leave fecal trails with an odor gradient, and other cockroaches follow those trails to food, water and hiding places. Across the group, a large number of species are gregarious or inclined to aggregate, and a slightly smaller number show parental care. Scientists once believed that aggregation was a reaction to environmental cues. They now believe pheromones are involved. Some species secrete these chemicals in their feces, with gut microbial symbionts taking part, while others use glands on their mandibles. Pheromones from the cuticle may let cockroaches tell different populations apart by odor. Simple interactions between individuals give rise to swarm behavior, which researchers call emergent behavior.
Scented roach-sized robots gave researchers a way to test how cockroaches choose a hiding place. Cockroaches appear to use just two pieces of information: how dark it is and how many other cockroaches are present. Once enough insects gathered to form a critical mass, the roaches accepted the group's choice of shelter, even an unusually lit spot. The same logic applies at food. When a quorum of individuals is exploiting a source, newcomers get the signal to stay longer rather than leave. Cooperation and competition stay balanced in these group decisions.
Lihoreau and fellow researchers noted evidence that a few group-living roaches in the genera Melyroidea and Aclavoidea may divide reproductive labor. If confirmed, these would be the only genuinely eusocial lineage known among roaches. By contrast, members of the genus Cryptocercus are subsocial.
In 2005, the protein pigment dispersing factor, or PDF, was isolated and found to be a key mediator of the cockroach's circadian rhythms. Cockroaches are mainly nocturnal and run away when exposed to light. The Asian cockroach is an exception. It flies mostly at night but is drawn to brightly lit surfaces and pale colors.
Gromphadorhina species and Archiblatta hoeveni make sound through modified spiracles on the fourth abdominal segment. Gromphadorhina produce several hisses. Adults and larger nymphs make disturbance sounds, while adult males make aggressive, courtship and copulatory sounds. Some other species buzz and some chirp. Henschoutedenia epilamproides has a stridulatory organ between its thorax and abdomen, though the purpose of its sound is unclear. Several Australian species use hisses and whistles, made by forcing air through the spiracles, as part of courtship. Some also tap the surface in a rhythmic, repetitive way near a potential mate. Acoustic signals may be more common among perching species on low vegetation in Australia's tropics.
A female German cockroach carries 30-40 long, thin eggs in a case called an ootheca. Laying the capsule can take more than five hours, and it starts out bright white. She drops it before hatching, though live births do occur in rare instances. The eggs hatch from the combined pressure of the hatchlings gulping air. The white nymphs keep inflating themselves, and within about four hours they become harder and darker. That brief white stage, seen at hatching and again during molting, has led to claims of albino cockroaches.
Development from eggs to adults takes 3-4 months, and cockroaches live up to a year. A female may produce up to eight egg cases in a lifetime. In favorable conditions that can mean 300-400 offspring. Other species can produce far more eggs, and in some cases a female needs to be impregnated only once to lay eggs for the rest of her life. Some adults have survived as many as four years in the laboratory.
The genus Diploptera is fully viviparous, giving birth to live young. Many other females attach the egg case to a surface, insert it into a protective crevice, or carry it until just before the eggs hatch. Some species are ovoviviparous, keeping the eggs inside the body until they hatch, with or without a case. Cockroaches have incomplete metamorphosis, so nymphs resemble adults apart from undeveloped wings and genitalia. Development is generally slow, taking from a few months to over a year.
Pheromones draw cockroach mates together, and males practice courtship rituals such as posturing and stridulation. The pair mate facing away from each other with their genitalia in contact, and copulation can be prolonged. A few species are parthenogenetic, reproducing without the need for males.
Female American cockroaches, Periplaneta americana, turn to parthenogenesis when housed in groups. This close association promotes the asexual production of oothecae, a type of egg mass. The process is called automixis. Meiosis still occurs, but instead of haploid gametes it yields diploid gametes, probably through terminal fusion, and these can develop into female cockroaches.
The American cockroach, Periplaneta americana, eats bread, fruit, leather, paper, glue, hair and skin flakes. It also takes dead insects, soiled clothing and the starch in book bindings. Many species harbor symbiotic protozoans and bacteria in the gut that digest cellulose, and in many species these partners may be essential. Some secrete cellulase in their saliva instead. The wood-eating cockroach Panesthia cribrata can survive indefinitely on crystallized cellulose while free of microorganisms.
All species studied so far carry the obligate mutualistic endosymbiont bacterium Blattabacterium, with one exception. Nocticola is an Australian cave-dwelling genus without eyes, pigment or wings, and recent genetic studies indicate it is a very primitive cockroach. Scientists had assumed that all five cockroach families descended from a common ancestor infected with B. cuenoti. Perhaps N. australiensis lost its symbionts later. Otherwise, the hypothesis will need to be re-examined.
Some species can remain active for a month without food and survive on meager resources such as the glue on the back of postage stamps. Some can go without air for 45 minutes. Nymphs of the Japanese cockroach, Crescispina japonica, hibernate in cold winters. In laboratory experiments they survived twelve hours at temperatures between minus 5 and minus 8 degrees Celsius.
Spiracles on every body segment connect to a branching system of tubes called tracheae. When carbon dioxide rises high enough, valves on the spiracles open, letting carbon dioxide out and oxygen in. The finest tubes, the tracheoles, carry air directly to each cell. Cockroaches have no lungs and can keep respiring if their heads are removed. In some very large species, the body muscles also contract rhythmically to push air in and out. Experiments on decapitated specimens found that shock avoidance and escape behavior remained, though many other insects survive decapitation too. Popular claims about how long headless cockroaches live do not appear to rest on published research. A severed head can survive and wave its antennae for several hours, and longer if refrigerated and given nutrients.
A lethal radiation dose for cockroaches is perhaps 6-15 times that for humans, which is far from the popular idea that they would inherit the Earth after a nuclear war. They are not exceptionally resistant compared with other insects, such as the fruit fly. The cell cycle explains the modest advantage. Cells are most vulnerable to radiation while dividing, and cockroach cells divide only once per molting cycle, which is weekly for a juvenile German cockroach. Not all cockroaches molt at the same time, so many would escape an acute burst. Prolonged radiation would still be harmful.
Four species account for most pest encounters. They are the German cockroach, Blattella germanica, the American cockroach, Periplaneta americana, the oriental cockroach, Blatta orientalis, and the brown-banded cockroach, Supella longipalpa. Pest species adapt readily and prefer the warm conditions inside buildings. They feed on human and pet food and can leave an offensive odor. They can also carry pathogenic microbes passively on their body surfaces, particularly in places such as hospitals.
Tropomyosin is one of the proteins that trigger cockroach allergy, and it can cause cross-reactive allergy to dust mites and shrimp. These allergens are also linked with asthma. A lack of sightings proves little. Approximately 20-48% of homes with no visible sign of cockroaches have detectable cockroach allergens in dust.
Baking soda has been suggested as a household remedy, with no evidence that it works. Garden herbs such as bay, catnip, mint, cucumber and garlic have been proposed as repellents. Poisoned bait containing hydramethylnon or fipronil, and boric acid powder, are effective on adults. Baits with egg killers also reduce the population. Insecticides containing deltamethrin or pyrethrin are very effective. In Singapore and Malaysia, taxi drivers use pandan leaves to repel cockroaches in their vehicles. Several published studies have advanced natural control with Metarhizium robertsii, also known as M. anisopliae.
Scientists at Purdue University concluded that the most common cockroaches in the US, Australia and Europe can develop "cross resistance" to multiple types of pesticide. That contradicted the earlier understanding that they develop resistance to one pesticide at a time. The scientists suggested that a diverse spectrum of chemical pesticides will no longer control cockroaches easily. They argued that traps and better sanitation will need to join the mix.
Ampulex wasps stalk cockroaches with a precise two-step attack. The first sting hits nerve ganglia in the thorax, causing temporary paralysis. A second, incapacitating sting goes into the brain. The wasp clips the antennae with its mandibles, drinks some hemolymph and drags the prey to a burrow. There it lays an egg, rarely two, on the cockroach, and the larva feeds on the subdued living prey. The ensign wasp Evania appendigaster attacks cockroach oothecae and lays a single egg inside. It is considered a promising candidate for biological control, and research continues on mass-rearing it for release. Widow spiders also commonly prey on cockroaches.
About an inch of water or stale beer, roughly two and a half centimeters, turns a deep, smooth-walled jar into a trap. Food goes inside, and a ramp of card or twigs leads to the opening. Stale beer is itself a cockroach attractant. The method works well with the American cockroach but less so with the German cockroach. Researchers from Heriot-Watt University have shown that a power laser can neutralise cockroaches in a home with high effectiveness. They suggest it might be an alternative to pesticides.
In Thailand and Mexico, cooks remove the heads and legs and then boil, sauté, grill, dry or dice the rest. Frying makes the insect crispy, with soft innards that taste like cottage cheese. Recipes from Taiwan call for it in omelets. Western culture considers this disgusting, yet cockroaches are eaten in many places around the world. Pest cockroaches may carry bacteria and viruses, but those bred under laboratory conditions can be used to prepare nutritious food.
About 100 cockroach farms in China raise the insects in large quantities for traditional medicine and cosmetics. Costs are relatively low because the insects are hardy and easy to process. Chinese and South Korean researchers are investigating cockroaches for treating baldness, AIDS and cancer, and as a dietary supplement. Recent experiments suggest that some species may also work as a plastic scavenger.
Laboratories favor cockroaches as insect models because they are large, resilient and easy to raise. They serve in neurobiology, reproductive physiology and social behavior, and in school and undergraduate biology classes. Experiments cover learning, sexual pheromones, spatial orientation, aggression, activity rhythms, the biological clock and behavioral ecology.
Aristotle mentioned a Greek insect called silphe that sheds its skin. It has been identified with the cockroach, though Silpha is the scientific name of a genus of carrion beetles. In Aristophanes' play Peace, the insect is foul-smelling. Euenus, in his Analect, called it a pest of book collections: "page-eating, destructive, black-bodied". Virgil named the cockroach "Lucifuga", meaning one that avoids light. Pliny the Elder recorded "Blatta" in various medicines, though he found the insect disgusting and a seeker of dark corners. Dioscorides recorded the silphe, ground up with oil, as a remedy for earache.
Lafcadio Hearn, who lived from 1850 to 1904, wrote of New Orleans that "For tetanus cockroach tea is given." He reported that faith in the remedy was strong among many of the American population there. A poultice of boiled cockroaches went over the wound. He added that cockroaches are eaten, fried with garlic, for indigestion.
The giant Madagascar hissing cockroach, Gromphadorhina portentosa, is the most commonly kept pet species, though enthusiasts keep many others. Species such as Blaptica dubia are raised as food for insectivorous pets. The Blattodea Culture Group thrived for about 15 years but now appears to be dormant. One member published Introduction to Rearing Cockroaches, which still appears to be the only book dedicated to the subject. A cockroach named Nadezhda flew on a Russian Foton-M mission, mated in space and produced 33 offspring after returning to Earth.
Pehr Osbeck, in a journal from 1750-1752, noted that cockroaches were frequently seen and found their way to the bakeries. This followed the sailing ship Gothenburg running aground and being destroyed by rocks. Donald Harington's satirical novel The Cockroaches of Stay More, published by Harcourt in 1989, imagines a community of "roosterroaches" in a mythical Ozark town. The insects are named after their human counterparts. Madonna has famously said: "I am a survivor. I am like a cockroach, you just can't get rid of me".
During the Rwandan genocide, Hutu militants used "cockroach" as a pejorative for Tutsis, in order to dehumanize them.
The Lord Howe Island wood-feeding cockroach, Panesthia lata, is listed as endangered by the New South Wales Scientific Committee. It may already be extinct on Lord Howe Island itself. Possible reasons for its scarcity include the introduction of rats, the spread of Rhodes grass, Chloris gayana, and fires. In the former Soviet Union, cockroach populations have been declining at an alarming rate, though this may be exaggerated or temporary or cyclic. One species, Simandoa conserfariam, is considered extinct in the wild.
The IUCN Red List lists Delosia ornata as endangered and Nocticola gerlachi as critically endangered. Both have restricted distributions and face habitat loss and rising sea levels. Only 600 Delosia ornata adults and 300 nymphs are known to exist, and a hotel development threatens them. No action has been taken to save either species, but protecting their natural habitats may prevent their extinction.
Updated
Common questions
How many species of cockroach are there and how many live with humans?
About 4,600 cockroach species and over 460 genera have been described worldwide. Only about 30 species are associated with human habitats, and four are most commonly encountered as pests.
Which cockroach is the heaviest and which is the longest?
The Australian giant burrowing cockroach, Macropanesthia rhinoceros, is the heaviest, reaching 8 cm in length and up to 35 g. The longest is Megaloblatta longipennis at 97 mm, and Megaloblatta blaberoides has the largest wingspan at up to 185 mm.
Are cockroaches related to termites?
Yes. Genetic evidence shows termites evolved directly from true cockroaches, and some cockroach groups are more closely related to termites than to other cockroaches. A hypothesis from 1934 linked termites to the wood-eating cockroaches of the genus Cryptocercus.
Would cockroaches survive a nuclear war?
Cockroaches have a lethal radiation dose perhaps 6-15 times that for humans, but they are not exceptionally resistant compared with other insects such as the fruit fly. Their cells divide only once per molting cycle, so many would escape an acute burst, though prolonged radiation would still be harmful.
How long do cockroaches live and how many offspring can they produce?
Cockroaches live up to a year, though some have survived as many as four years in the laboratory. A female German cockroach may produce up to eight egg cases in a lifetime and, in favorable conditions, 300-400 offspring.
Which cockroach species are the most common household pests?
The four most common pest species are the German cockroach (Blattella germanica), the American cockroach (Periplaneta americana), the oriental cockroach (Blatta orientalis) and the brown-banded cockroach (Supella longipalpa).
Are any cockroach species endangered?
Yes. The IUCN Red List lists Delosia ornata as endangered and Nocticola gerlachi as critically endangered, and Simandoa conserfariam is considered extinct in the wild. Only 600 Delosia ornata adults and 300 nymphs are known to exist.
All sources
129 references cited across the entry
- 3Blattodea: roaches - Univ. of Minnesota Insect CollectionThom1514 — 27 August 2014
- 5Cockroach Species File Online. Version 5.0Beccaloni, G. W. — 2014
- 6Blattodea (Cockroaches & Termites)CSIRO Entomology
- 7BookA Dictionary of EntomologyG. Gordh et al. — CABI — 2009
- 8BlattaCharlton T. Lewis et al. — Tufts University
- 9JournalA fossil mantis (Insecta, Mantodea) in Cretaceous amber of New Jersey: with comments on the early history of the DictyopteraD. Grimaldi — 1997
- 10JournalX-ray micro-tomography of Carboniferous stem-Dictyoptera: new insights into early insectsR. Garwood et al. — 2010
- 11BookEvolution of the InsectsDavid Grimaldi et al. — Cambridge University Press — 2005
- 12JournalTomographic Reconstruction of Neopterous Carboniferous Insect NymphsR. Garwood et al. — 2012
- 13JournalMesozoic origin-delayed explosive radiation of the cockroach family Corydiidae Saussure, 1864P. Vršanský et al. — 2022
- 14JournalLate Mesozoic cockroaches s.l. from the Karabastau Formation in KazakhstanP. Vršanský — 2024
- 15JournalDeath of an order: a comprehensive molecular phylogenetic study confirms that termites are eusocial cockroachesD. Inward et al. — 2007
- 16JournalOrder Blattodea. In: Zhang, Z.-Q. (Ed.) Animal Biodiversity: An Outline of Higher-level Classification and Survey of Taxonomic Richness (Addenda 2013)George Beccaloni et al. — 2013
- 17JournalThe Wood-Feeding Roach Cryptocercus, Its Protozoa, and the Symbiosis between Protozoa and RoachL. R. Cleveland et al. — 1934
- 18JournalA contribution to the understanding of cockroach-termite affinitiesF.A. McKittrick — 1965
- 19JournalResponse to Lo et al.Paul Eggleton et al. — 2007
- 20JournalSave Isoptera: A comment on Inward et al.Nathan Lo et al. — 2007
- 21Pet facts: giant burrowing cockroachesAustralian Broadcasting Corporation
- 22JournalGenome Sequence of Blattabacterium sp. Strain BGIGA, Endosymbiont of the Blaberus giganteus CockroachC. Y. Huang et al. — 2012
- 23Largest cockroachGuinness World Records
- 24Cockroaches hit the shelvesNatural History Museum — May 2006
- 25JournalA New Myrmecophile from the Mushroom Gardens of the Texan Leaf-Cutting AntWilliam Morton Wheeler — November 1900
- 27BookIntroduction to Insect Biology and DiversityH. V. Hoell — Oxford University Press — 1998
- 28JournalConvergent evolution and locomotion through complex terrain by insects, vertebrates and robotsRoy E. Ritzmann et al. — 2004
- 29JournalDistributed mechanical feedback control of rapid running on challenging terrainJ. C. Spagna et al. — 2007
- 30BlattodeaJ. Meyer — University of North Carolina
- 31Cockroaches: Order BlattodeaAustralian Museum — 13 January 2012
- 32JournalComparative insecticide susceptibility and detoxification enzyme activities among pestiferous blattodeaS. M. Valles et al. — 1999
- 33JournalIntegrated suppression of synanthropic cockroachesC. Schal et al. — 1990
- 34"10 Fascinating Cockroach Facts"National Pest Management Association
- 35BookCockroaches: Ecology, Behavior, and Natural HistoryWilliam J. Bell et al. — JHU Press — 2007
- 36BookThe Other Insect SocietiesJames T. Costa — Harvard University Press — 2006
- 37JournalChronobiological analysis and mass spectrometric characterization of pigment-dispersing factor in the cockroach Leucophaea maderaeYasutaka Hamasaka et al. — 22 December 2005
- 38CockroachesRust, M. K. — University of California — 2007
- 39Asian cockroachRichman, Dina L. — University of Florida — 1 June 2014
- 40JournalCollective foraging decision in a gregarious insectLihoreau, Mathieu et al. — 2010
- 41JournalCockroach aggregation based on strain odour recognitionJean-Marc Ame — Oct 2004
- 42JournalSelf-organized aggregation in cockroachesRaphael Jeanson — Jan 2005
- 432008 IEEE Swarm Intelligence SymposiumTimothy C. Havens et al. — IEEE — 2008
- 44MagazineRobotic Roaches Do the TrickMichael D. Lemonick — 15 November 2007
- 45JournalThe weight of the clan: Even in insects, social isolation can induce a behavioural syndromeLihoreau, Mathieu et al. — 2009
- 46JournalGroup personality during collective decision-making: a multi-level approachIsaac Planas-Sitjà — 2015
- 47NewsEven cockroaches have personalitiesVirginia Morell — 3 February 2015
- 48JournalThe social biology of domiciliary cockroaches: colony structure, kin recognition and collective decisionsM. Lihoreau — November 2012
- 49JournalNeotropical Melyroidea group cockroaches reveal various degrees of (eu)socialityJan Hinkelman et al. — 2020
- 50JournalSound production in the cockroach, Gromphadorhina portentosa: The sound-producing apparatusNelson, Margaret C. — 1979
- 51JournalSound production and reception in a cockroachGuthrie, D.M. — 1966
- 52BookA Guide to the Cockroaches of AustraliaDavid Rentz — CSIRO Publishing — 2014
- 53BookAmerican CockroachWilliam J. Bell et al. — Springer — 1981
- 54JournalCellulose digestion in termites and cockroaches: What role do symbionts play?Michael Slaytor — 1992
- 55JournalTermites and trees: a review of recent advances in termite phylogeneticsP. Eggleton — 2001
- 56JournalEvidence for Cocladogenesis Between Diverse Dictyopteran Lineages and Their Intracellular EndosymbiontsN. Lo et al. — 2003
- 57NewsCave may hold missing linkLeung, Chee Chee — 22 March 2007
- 58JournalCockroaches that lack Blattabacterium endosymbionts: The phylogenetically divergent genus NocticolaN. Lo et al. — 2007
- 59The Cockroach FAQUniversity of Massachusetts
- 60JournalGroup-housed females promote production of asexual ootheca in American cockroachesK. Katoh et al. — 2017
- 61JournalFirst molecular genetic evidence for automictic parthenogenesis in cockroachesM. Tanaka et al. — 2019
- 62BookMedical and Veterinary EntomologyAcademic Press — 2002
- 63JournalWinter Survival and Freeze Tolerance in a Northern Cockroach, Periplaneta japonica (Blattidae: Dictyoptera)K. Tanaka et al. — 1997
- 64BookThe Earwig's Tail: A Modern Bestiary of Multi-legged LegendsMay Berenbaum — Harvard University Press — 30 September 2009
- 65NewsFact or fiction?: a cockroach can live without its headCharles Choi — 15 March 2007
- 66Cockroaches and RadiationKruszelnicki, Karl S. — ABC Science — 23 February 2006
- 67BookThe Laboratory Cockroach: Experiments in cockroach anatomy, physiology and behaviorW. J. Bell — Springer — 2012
- 68Cockroaches: The insect we're programmed to fear18 September 2014
- 69BookThe Insects: An Outline of EntomologyP. J. Gullan et al. — Wiley — 2014
- 705 Common Types Of CockroachesEmily Glover — 30 July 2024
- 71Common Pest Cockroaches20 Mar 2024
- 72JournalHealth Implications of Cockroach InfestationsR.J. Brenner et al. — 1987
- 73JournalBacterial load of cockroaches in relation to urban environmentC. Rivault et al. — 1993
- 74JournalCarriage by the German cockroach (Blattella germanica) of multiple-antibiotic-resistant bacteria that are potentially pathogenic to humans, in hospitals and households in Tripoli, LibyaR.M. Elgderi et al. — 2006
- 75JournalInsect Allergy Preliminary Studies of the CockroachH.S. Bernton et al. — 1964
- 76JournalCockroach Infestation in Some Hospitals in Trabzon, TurkeyB Kutrup — 2003
- 77JournalCockroach allergens and asthma in Brazil: identification of tropomyosin as a major allergen with potential cross-reactivity with mite and shrimp allergensSantos AB, Chapman MD, Aalberse RC, Vailes LD, Ferriani VP, et al — 1999
- 78JournalCockroach cause of allergic asthma. Its specificity and immunologic profileB. Kang et al. — 1979
- 79JournalEcology and elimination of cockroaches and allergens in the home.P.A. Eggleston et al. — 2001
- 82CockroachesAlamance County Department of Environmental Health
- 83Pandan leaves (Pandanus amaryllifolius Roxb.) As A Natural Cockroach RepellentLi J. and Ho S.H. — School of Biological Sciences, National University of Singapore
- 84JournalReview on safety of the entomopathogenic fungus Metarhizium anisopliaeGisbert Zimmermann — Taylor & Francis — 2007
- 85JournalNotes on the Biology and Behaviour of the Jewel Wasp, Ampulex compressa (Fabricius, 1781) (Hymenoptera; Ampulicidae), in the Laboratory, Including First Record of Gregarious ReproductionEduardo Gonçalves Paterson Fox et al. — September 2009
- 86JournalOn the morphology of the juvenile stages of Ampulex compressa (Fabricius 1781) (Hymenoptera, Ampulicidae)Eduardo G P Fox et al. — 3 August 2006
- 87BookExtraordinary Animals: An Encyclopedia of Curious and Unusual AnimalsPiper, Ross — Greenwood Press — 2007
- 88Evania appendigaster DevelopmentEduardo G P Fox — 10 May 2011
- 89JournalThe preimaginal stages of the ensign wasp Evania appendigaster (Hymenoptera, Evaniidae), a cockroach egg predatorEduardo Gonçalves Paterson Fox et al. — June 2012
- 90JournalThermal requirements for the embryonic development of Periplaneta americana (L.) (Dictyoptera: Blattidae) with potential application in mass-rearing of egg parasitoidsS. Bressan-Nascimento et al. — December 2008
- 91JournalEffects of different temperatures on the life history of Evania appendigaster L. (Hymenoptera: Evaniidae), a solitary oothecal parasitoid of Periplaneta americana L. (Dictyoptera: Blattidae)S. Bressan-Nascimento et al. — February 2010
- 92What Do Black Widows Eat?11 April 2018
- 94BookMedical and Veterinary EntomologyHerms, William Brodbeck — MacMillan — 1915
- 95NewsCockroaches could soon be almost impossible to kill with pesticidesCalla Wahlquist — 3 July 2019
- 96JournalSelective neutralisation and deterring of cockroaches with laser automated by machine visionIldar Rakhmatulin et al. — 3 April 2023
- 103Taiwanese man creates culinary masterpiece: cockroach omeletPhillip Charlier — 23 June 2023
- 105NewsA giant indoor farm in China is breeding 6 billion cockroaches a year. Here's whyStephen Chen — 19 April 2018
- 106NewsCockroach farms multiplying in ChinaBarbara Demick — 15 October 2013
- 107JournalCockroach Blaptica dubia biodegrades polystyrene plastics: Insights for superior ability, microbiome and host genesLi MX, Yang SS, Ding J, Ding MQ, He L, Xing DF, Criddle CS, Benbow ME, Ren NQ, Wu WM — November 5, 2024
- 108Lord Howe Island wood-feeding cockroach – endangered species listingGovernment of New South Wales — 2011
- 109Delosia ornataJ. Gerlach — 2012
- 110Nocticola gerlachiJ. Gerlach — 2012
- 111NewsИсчезновение тараканов на Белгородчине не связано с радиацией4 December 2006
- 112JournalA new genus and species of cave cockroach (Blaberidae: Oxyhaloinae) from Guinea, West AfricaLouis M. Roth et al. — 2004
- 113BookA Dictionary of Greek and Roman AntiquitiesCharles Anthon — American Book Company — 1843
- 114BookNatureNorman Lockyer — Macmillan Journals — 1871
- 115BookInventing New Orleans: Writings of Lafcadio HearnLafcadio Hearn et al. — University Press of Mississippi — 2001
- 116JournalInstar Determination of Blaptica dubia (Blattodea: Blaberidae) Using Gaussian Mixture ModelsHao Wu et al. — 2013
- 117Madagascar Hissing Cockroaches: Information and CareMulder, Phil — Oklahoma 4-H Youth Development. Oklahoma State University
- 119Bragg, P.E. (1997) An Introduction to Rearing Cockroaches. P.E. Bragg, Ilkeston.
- 121JournalGraded Exposure Therapy for Long-Standing Disgust-Related Cockroach Avoidance in an Older MaleDavid Berle — August 2007
- 122JournalMixing Realities? An Application of Augmented Reality for the Treatment of Cockroach PhobiaC.M. Botella et al. — 2005
- 123BookInsects: their biology and cultural historyB. Klausnitzer — Universe Books — 1987
- 125Madonna
- 126NewsCockroaches are not radiation-proof and most are not pestsBBC Earth
- 127NewsCockroaches are not radiation-proof and most are not pestsThird party appears to have reposted the original, for which the original URL doesn't seem to work. — 4 October 2016
- 128JournalDevelopment and the availability of food in the German cockroach, Blattella germanica (L.)Joseph G. Kunkel — February 1966