WARNING: SCUTIGERA COLEOPTRATA IMAGES BELOW
In 1902, C.L. Marlatt of the Department of Agriculture’s Division of Entomology published the following description of our favorite chilopod: “It may often be seen darting across floors with very great speed, occasionally stopping suddenly and remaining absolutely motionless, presently to resume its rapid movements, often darting directly at inmates of the house, particularly women, evidently with a desire to conceal itself beneath their dresses, and thus creating much consternation.” Of all the creepy crawlies worthy of the name, the scutigera coleoptrata (Linnaeus 1758) may very well take the crown for creepiest, going so far as to claim our private space as its colloquial name: the house centipede.
Kingdom: Animalia (Animals)
Phylum: Arthropoda (Arthropods)
Subphylum: Myriapoda (Myriapods)
Class: Chilopoda (Centipedes)
Order: Scutigeromorpha (House Centipedes)
It is believed that the house centipede originated in the Mediterranean region but eventually found its way into Europe, Asia, and North America. In colonial North America, the house centipede likely made landfall in Mexico and southern states, preferring damp, humid environments. From here, the creature began a northward migration up the east coast. It had been observed in Pennsylvania as early as 1849, New York in 1885, and Massachusetts by 1890. In Bulletin No. 46 of the Smithsonian’s National Museum, published in 1893, the centipede’s geographic distribution was listed as “E n, E s,” marking a distinct preference for the humid environment of many eastern seaboard states. Marlatt states that by 1902 the centipede was “now very common through New York and the New England States, and extends westward well beyond the Mississippi, probably to the mountains.” Modern accounts confirm it has reached the Pacific. Marlatt relays that the centipede, “particularly within the last ten or twelve years, has become altogether too common an object in dwelling houses in the Middle and Northern States for the peace and mind of the inmates.”
The class Chilopoda includes four orders, Scutigeromorpha, Lithobiomorpha, Scolopendromorpha, and Geophilomorpha. While all four orders are found in the United States, the house centipede is one of only two scutigeromorphs found north of Mexico, the other being scutigera linceci as reported in the 1887 Proceedings of the United States National Museum. Of the few thousand kinds of centipedes known to mankind, the house centipede is the only one capable of completing its entire life cycle indoors. It is this distinctly domestic existence that distinguishes this house dweller from its companions, and may explain why it takes the crown for invoking fear and alarm among people today.
Taxonomist Constantin Samuel Rafinesque-Schmaltz, whom entomologists Richard L. Hoffman and Ralph E. Crabill, Jr. have called one of the “true pioneers of American zoology,” is credited with being the first to describe the scutigera coleoptrata in detail. In his description, published in The Annals of Nature (1820), Rafinesque remarks, “Found near Baltimore by Mr. H. Hayden. It comes into the houses, length one inch.” Thus from the earliest known description in 1820, scutigera coleoptrata has been associated with the home. Marlatt describes these critters as “creatures of the damp,” though they do not travel through pipelines. Rather, they inhabit the cracks and crevices between walls and concrete slabs that comprise home foundations. They are commonly found in bathrooms and basements due to the higher humidity in such rooms. Marlatt states that “in houses it will often be dislodged from behind furniture or be seen to run rapidly across the room, either in search of food or concealment.”
The house centipede’s appearance is not for the faint of heart. The animal’s yellowish brown body segment, which can generally grow to an inch or more in length, is marked by three dorsal longitudinal dark stripes. Unlike most centipedes, scutigera coleoptrata has well-developed, compound eyes. An adult centipede has fifteen pairs of legs, the last of which (in females) run nearly twice the length of the body and function as rear antennae. The legs and antennae give the centipede a much larger appearance, reaching three to four inches in fully grown adults. The front pair of legs serves as modified fangs, which inject venom into its prey. While house centipedes have been known to bite humans in self-defense, their fangs rarely penetrate skin, and even when successful, cause no more harm than a bee sting.
The chief characteristic by which the house centipede evokes terror, however, is its uncanny speed. The centipede’s legs grow progressively longer towards the rear of its body, allowing rear legs to cross above and to the outside of those in front of them, preventing entanglement. A lung-like tracheal system unique among chilopods enables the creature to oxygenate fully during movement. As its legs ripple in what author Richard L. Jones describes as “undulating synchrony,” the centipede appears as if it is levitating across the surface, rather than running. Dr. Arthur V. Evans notes that house centipedes sprint at “speeds of 420 mm/second; a 5’8” human would have to run the same distance, relative to their height, at a speed of about 42 miles/hour.” (Usain Bolt’s record is 27.8 miles/hour.) As the 1976 Guinness Book of World Records states, the house centipede is the world’s fastest arthropod—roughly 16 inches per second.
It is the speed, coupled with the inherent notion that it moves within the private space of our home, that causes a heightened sense of situational anxiety upon seeing the house centipede scurry across a wall—our wall—ceiling, or floor. Our spatial understanding of the human relationship to the natural world is widely divergent depending on the exact environment in which these encounters occur. Whereas in a total wilderness environment, such as that of a rainforest, we expect to come across such unsavory creatures, in the safety of our homes such unexpected encounters can be disturbing. Here, we as homeowners set the rules of the house, granting permission to those we wish to enter while denying permission to the rest. When a house centipede shows up on our wall uninvited, fear derives not only from the creature’s appearance, but the inherent resignation that our personal space has been breached by an unwelcome intruder.
Such experiences have invoked fear in the hearts and minds of homeowners for years. Their rapid movement and disregard for human interference has brought even the stoutest of heart to their knees. Beat Generation writer William S. Burroughs went so far as to say this of centipedes through his protagonist in The Western Lands (1987):
“Let me confess that I hate centipedes, above all other creatures on this horrid planet. And I am not alone in this aversion. Many others have confessed to me that they hold a special antipathy for this creature, which is so far removed from the mammalian mold. … There may be people who like centipedes. I have seen people handling tarantulas and scorpions, but never a centipede handler. Personally, I would regard such an individual with deep suspicion. … Now what sort of man or woman or monster would stroke a centipede on his underbelly? ‘And here is my good big centipede!’ If such a man exists, I say kill him without more ado. He is a traitor to the human race.”
While Burroughs may be the most famous to loath centipedes, he is not alone. A quick google search of the creature will reveal not only a collection of images you may wish to have never seen, but a number of articles with unending comment sections that function as something akin to group therapy sessions. Commenters all share one thing in common, a traumatic domestic encounter with our favorite chilopod. Yet for all the fear they bring about, what purpose do house centipedes serve?
The house centipede sits atop the food chain in the artificially-built environment. Their diet, hunted nocturnally, consists of all the pests that homeowners abhor, including cockroaches, silverfish, spiders, flies, moths, and all sort of other small insect. It can capture multiple prey at once. J.G.E. Lewis records in The Biology of Centipedes that one centipede caught its victims by “half pouncing, half lassoing them: as many as five flies were captured at one time and held between the quivering, lashing appendages. Immobile while awaiting prey, the cursorial appendages maintain a constant fluttering tremor while the animal feeds.” Despite its ghastly appearance, Marlatt acknowledges that the house centipede seems to be “a very efficient enemy of many of our house pests.”
House centipedes do not feed off human habits directly, but their diet consists of those that do, making them the first line of defense against a potential large infestation. Not only the centipedes, but the cockroaches, silverfish, and other arthropods on which they feed are synanthropic, or ecologically associated with humans. A synanthrope (from the Greek syn-, “together with” + anthro, “man”) is a species of wild animal (or plant) that lives near, and benefits from, an association with humans and the artificial habitats they create and inhabit, such as houses, farms, gardens, and garbage dumps.
Ecosystems do not stop at our doorstep. Urban wildlife, such as raccoons, rats, coyotes, and pigeons, reveals that many animals make no distinction between nature and artifice when trying to survive. Homes are no different, especially when our living habits make us direct participants in their domestic ecology. If a house centipede’s natural food source exists in the kitchens, cellars, and bathrooms of human residences, its presence is justified.
While many who fear the house centipede may wish for their complete eradication, history warns us against such futile attempts. A popular theory in rationalizing dramatic change in ecosystems is that of trophic cascades, which demonstrate the potential negative snowball effect human interference with the natural order can have. Take Yellowstone, for example, where the eradication of predatory wolves unraveled a number of problems, including a ballooning elk population that ravaged shoreline willows. The willows’ deep roots provided beavers with food and raw materials to build dams, and also helped slow the stream of water which facilitated dam building. With no wolves to curb an herbivorous elk population, beavers were without the industrious resource on which they so heavily relied. As the beaver population plummeted, extant willows could no longer root in sediment generated by their dams. What has resulted is a completely altered ecology in Yellowstone, with beaver and willow populations still struggling to recover today, despite the reintroduction of wolf populations.
Unforeseen casualties of house centipede eradication could wreak havoc in domestic ecosystems with a far more immediate impact on homeowners than those seen in Yellowstone. If we are to consider ourselves the top level predator in our own homes, capable of killing house centipedes not for sustenance, but for peace of mind, their elimination by our hand could alter the larger food web ecology of interior environments. This portends not only an influx of more harmful pests, but the possibility of an even less-hospitable living environment and costlier exterminator bills. Rather than view these encounters as biological invasions of our private space, a great deal of fear and misunderstanding might be alleviated in the acknowledgment of our homes as domestic ecosystems, in which we as humans are primary players. The control we exert over our private living space may not always include which creature can and cannot enter, but we can control how we view such inherent biodiversity. This is key to overcoming our fears and coexisting with such creatures, whether it be willingly, or with a shudder as we tell a loved one to take care of the problem.
Gerald Summers, “An Illustrated Key to the Chilopods of the North-Central Region of the United States,” in Journal of the Kansas Entomological Society, vol. 52, no. 4 (1979): 690-700.
J.G.E. Lewis, The Biology of Centipedes, London: Cambridge University Press, 1981.
Richard Jones, House Guests, House Pests: A Natural History of Animals in the Home, New York, NY: Bloomsbury Publishing USA, 2015.
Richard L. Hoffman and Ralph E. Crabill, Jr., “C. S. Rafinesque as the Real Father of American Myriapodology: An Analysis of His Hitherto Unrecognized Species,” in The Florida Entomologist, vol. 36, no. 2 (June, 1953): 73-82.