Every so often, a media outlet reports someone finding a spider or an egg sac in a shipment of bananas (or other international cargo). The article typically screams about potentially death-dealing spiders or spiderlings unleashed upon an unsuspecting general public in typical Hollywood 72-point type. The message is almost never one of subtlety or scientific validity. Often people who do not have any arachnological skill other than to surf the Internet (which is full of misinformation) misidentify the harmless spider as being one of a “deadly” species.
Being called upon to deal with this episode may be a once-in-a-career event for a pest control professional, however, the hyperbolic reaction of people and the media make this a high-profile situation. Therefore, having the correct information could be invaluable to prevent misidentifications (and the calling of the cavalry). The following article summarizes a recent study published in the Journal of Medical Entomology on spiders brought into North America in international cargo.
Brazilian Wandering Spider.
The spider most discussed in these hyperbolic media and Internet articles is the Brazilian wandering spider, Phoneutria fera. It is presented as a highly toxic monster, resulting in overreaction by the unknowing public. Much of this is due to the fact that because spiders found in bananas are from Central and South America, almost no entomologists and very few arachnologists have, until recently, had any literature on the subject. An “expert” is then pressed for a quick identification from a worried homeowner or grocery store employee.
One of the more commonly intercepted spiders has red hairs on its face. This spider is often misidentified as a Brazilian wandering spider from either Internet images or a children’s spider book. And the spider is described as “deadly” or “poisonous” (although the correct term is actually “toxic”).
In reality, it is extremely unlikely that this species of Brazilian wandering spider would be brought to North America in bananas. First, it lives in the Amazon, far from the Brazilian banana-growing areas in the eastern coastal regions. Second, North America gets 96 percent of its bananas from Central America and northwestern South America (Ecuador, Colombia), not Brazil. Third, Brazil consumes most of its crop domestically so there is little left for export.
In addition, the medically important Brazilian wandering spiders that are highly dangerous are limited to the eastern Brazilian coastal region and despite all the hype and hoopla, are not nearly as “deadly” as they have been made out to be. A report of 422 bites by eastern Brazilian wandering spiders in humans did denote one death in a small child (so they aren’t harmless) but no adults died from a bite and more than 80 percent of the bite victims reported no or minor symptoms. One mitigating factor though is that a smaller species of wandering spider (30 mm in body length compared to 50 mm for the eastern Brazilian species) lives in Ecuador, Colombia and southern Central America and on rare occasion is transported to North America in bananas (Fig. 1). However, this species is considered less toxic than its larger relatives. Reports of bites to banana plantation workers reported no deaths and workers typically missed two or three days before returning to their jobs. So overall, the probability of “deadly Brazilian wandering” spiders showing up in bananas brought to North America is minuscule.
People are freaked out when they unpack fruit in the store and a long-legged critter comes romping out. And the most common large spider brought into North America on bananas in the 2014 study was the pantropical huntsman spider, Heteropoda venatoria (about 3- to 3½-inch leg span) (Fig. 2).
This creature is found throughout the tropics worldwide including Hawaii, Florida, Taiwan, Hong Kong, Australia, Uganda, Ecuador, etc. It is a harmless spider with long legs rotated to the side so it looks somewhat like a crab. The females are mostly uniformly brown in color whereas the male has a lovely splashing of tan, brown and black markings. However, both sexes have a white “mustache” above the mouthparts and below the eyes.
The other most commonly intercepted spiders are those of the genus Cupiennius. These are large (about 3-inch legspan) and have coloration that allows one to easily identify them. They come from Central America (Guatemala, Costa Rica and Nicaragua). Their bites are of little concern, most becoming asymptomatic within hours.
The most common species that is intercepted is the redfaced banana spider, C. chiapanensis. This spider has bright red hairs on the upper two-thirds of its chelicerae (the mouthparts that house the fangs) (Fig. 3). This spider is most frequently mistaken for a Brazilian wandering spider. It was only scientifically described in 2006 so arachnologists were not aware of its existence, which is why many misidentifications were made years ago.
However, there are many websites and other sources that mistakenly identify the redfaced banana spider as potentially deadly, causing unwarranted panic and arachnophobia.
A lesser-found species is the spotlegged banana spider, C. getazi, which has black dots on a white background on the underside of the leg segments closest to the body (Fig. 4). Finally, the redlegged banana spider, C. coccineus, is occasionally found in bananas. It has bright red hairs on the underside of the leg segments closest to the body on the first two pair of legs.
In addition to spiders, occasionally egg sacs deposited on bananas are discovered by supermarket employees or by customers when they unpack the fruit at home. Most of these egg sacs have been smashed into oblivion during transport, however, sometimes, the egg sac contains uncrushed eggs or live spiderlings. Once again, people panic. And predictably, even though non-arachnologists have no experience identifying egg sacs (which are incredibly difficult to identify to species even by arachnologists because there is even less scientific literature on this topic than for spiders), the egg sacs are positively “identified” by amateurs as belonging to the “deadly” Brazilian wandering spider.
Of the 20 or so egg sacs that have been submitted to me for identification, almost all were pulverized into flatness and the ones that weren’t had 50 to 200 eggs. The species of wandering spider that has shown up on rare occasion in bananas shipped to North America lays an average of 850 eggs per sac. Therefore, the egg sacs arriving with bananas so far surely are not that of wandering spiders. Attempts to rear the spiderlings to adulthood have failed; these spiderlings look closest in identity to a small species not known to be harmful.
The overall conclusions from the study were:
- Almost all spiders transported to North America in bananas are medically benign.
- Most wandering spider bites are not fatal.
- The species of wandering spider from northwestern South America that is rarely found in bananas is smaller than the dangerous Brazilian species and its bites do not result in death.
- The wandering spiders of medical importance are found in Brazil, which doesn’t export a significant amount of bananas anywhere and possibly none to North America.
- Egg sacs found on bananas are not from wandering spiders but their identity is currently not known.
Vetter, R.S. and S. Hillebrecht. 2008. On distinguishing two often-misidentified genera (Cupiennius, Phoneutria) (Araneae: Ctenidae) of large spiders found in Central and South American cargo shipments. American Entomologist 54: 82-87.
Vetter, R. S., R. L. Crawford and D. J. Buckle. 2014. Spiders (Araneae) found in bananas and other international cargo submitted to North American arachnologists for identification. Journal of Medical Entomology 51: 1136-1143.
The author is a retired staff research associate with the University of California, Riverside, and one of the country’s leading authorities on spiders.
There is simply no chance for spider eggs to get into a banana. Nor would a species that did this survive long, since spiderlings in an uneaten banana could never escape. Not that eating spider eggs would cause any harm even if this fantasy were true! This myth has already spawned variations.What spider do you find in bananas? ›
Its scientific name, Phoneutria, translate as “murderess” in Greek. Like the wandering spider, the one in Stein's bananas had a body length of around two inches and was covered in brown hair.Why are they called banana spiders? ›
What are banana spiders? Banana spiders are large spiders found throughout the southeastern United States. Banana spiders receive their name because of the yellow/golden-colored silk they create to make their very large webs which they use to catch flying insects, their main food source.What do you do if you find spider eggs on a banana? ›
"If you do find eggs on your bananas, the best thing to do is wash them off, if you are really worried you could put them in the freezer to kill them - then enjoy your banana!" Buglife also has lots of information about spiders found on bananas on their website, here.What month do banana spiders come out? ›
FIGURE 4. Banana Spiders prey on a wide variety of medium to small size flying insects including leaf-footed bugs (pictured above) and mosquitoes. Occurrence: Widespread (i.e., notably visible) across the county from mid-summer to late fall.Can a banana spider hurt you? ›
Most banana spiders are not dangerous to humans. The Brazilian wandering spider is more venemous than others, but it rarely appears in international shipments. Spiders typically don't bite humans unless held or threatened. A bite from any type of banana spider may cause pain or irritation, but it's not usually deadly.Where is the banana spider found? ›
Brazilian wandering spiders live in South and Central America. Sometimes, these spiders make their way into other countries on fruit shipments. However, these pests mostly live in the Amazon, where they see little human contact. Cupiennius banana spiders are more widespread in Central America.Why do spiders go in bananas? ›
“In the 1950s, it was common for people to find insects in bananas, then it became less common. This is the cost of reducing pesticides.” Bunches of fruit provide a perfect environment for creepy crawlies to hide in, says Barclay - which also explains why black widow spiders are sometimes found in bunches of grapes.What happens if a banana spider bites you? ›
A bite from the banana spider (also known as the Brazilian wandering spider) of Central and South American rain forests causes shortness of breath, excessive salivation, tremors and—for men—a persistent, intensely painful erection, known as priapism in the medical community.Where did banana spiders come from? ›
Native to Central and South America, Cupiennius is a genus of spiders broadly called banana spiders because bananas are the plants on which these spiders are most often found. What is this? It's quite common for workers in other countries to discover these spiders in imported banana shipments.
But lest you be tempted to "taste the rainbow," please hold back, as some spider eggs are known to be toxic, according to a study published in August 2017 in the Journal of Arachnology.Can spider eggs hatch inside human body? ›
Myth: Spiders can lay their eggs under human skin in wounds created by their bites. Fact: In a surprisingly widespread urban legend, a nameless woman is bitten by a spider (usually on her cheek) while on vacation. She later develops a swelling, from which, in due course, baby spiders emerge!How long does it take a banana spiders eggs to hatch? ›
Eggs take about 2 weeks to hatch. During this time, the spider will sometimes move the sac around the web and obscure it from view, most likely as a defense mechanism. Once the eggs are hatched, the spiderlings occupy a communal web while they mature.What spider can paralyze you? ›
A Brown Recluse Spider Bite Caused A Woman To Hallucinate And Become Paralyzed, And There Are Dozens More Hiding In Her Home. The brown recluse spider may not look intimidating, but it is one of the most dangerous spider species in the United States.What is a big spider called? ›
Nope! Banana peels are totally edible, if prepared correctly. Bananas are known for their high potassium content, with each medium fruit containing a whopping 422 milligrams. The peel contains an additional 78 milligrams of potassium, plus plenty of filling fiber.What happens if you are bitten by a black widow spider? ›
The black widow spider makes a venom that affects your nervous system. Some people are slightly affected by it, but others may have a severe response. Right away, you may feel severe pain, burning, swelling, and redness at the site. You may even see two fang marks.Why are banana spiders so big? ›
Appearance: How To Identify Banana Spiders
A very large female can have a leg span that's over 5 inches, and they grow even bigger around human habitation due to the availability of prey. Males and females both have eight legs and slender bodies, though a gravid female's abdomen is round like a gumball.
In Cambodia, fried tarantulas are a delicacy. Often rolled in sugar or garlic, the spiders are eaten by the handful out of street vendors' carts by local residents and adventurous tourists alike.
Spiders are free living predators. They are not parasites.. They hunt and trap small prey. There aren't even any arachnids that can lay their eggs INSIDE of humans.What color is a spider egg? ›
Spider egg sacs are usually white to cream in color and will be either round or oblong in shape. Some egg sacs are smooth, while others may contain spikes or bumps. Black widow eggs are small, about the size of a pencil eraser.Can spiders live in your hair? ›
So have spiders been found to dwell within human hair? There is probably not even a grain of truth to these stories, and as you can guess, spiders do not find the human scalp, with its rows of hair, an ideal place to lay their eggs.Do spiders shoot sperm? ›
If courtship is successful, the male injects his sperm from his palps into the female's genital opening, known as the epigyne, on the underside of her abdomen.Can spiders track humans? ›
Stimulus forces in the . 01 near-undetectable range are enough for spider stimulation, according to a new published in the Journal of the Royal Society Interface. In fact, a spider's entire body is built to detect almost anything and anyone that might cross its path.Are banana spiders rare? ›
Fortunately, this spider species is exceptionally infrequently encountered in the U.S. Spiders possessing the common name banana spiders found in the U.S. are able to bite, but their bite is not as harmful or painful as bites from other spiders, like the brown recluse or black widow spider.Can you move spider eggs? ›
Spider eggs are fragile and can be removed with a broom or vacuum cleaner. If using a vacuum, remove the bag after each cleaning and dispose of the debris, including the eggs, in a sealed plastic bag.Do baby spiders stay with their mother? ›
After 40 days, mothers no longer provide milk, but the spiderlings continue to live at home. (For a thriving brood, the authors suggest mother spiders keep their nests clean and free of parasites.) Offspring only leave the nest at about three months, long after they are mature adults.Are there spiders in banana boxes? ›
Terrified store staffers found huge tropical spiders in two fruit boxes in Germany. A huge, venomous tropical spider with a skull on its back has been found in a second supermarket in Germany by terrified workers. Both were found in a box of bananas from the Dominican Republic.Are there spiders in banana trees? ›
Native to Central and South America, Cupiennius is a genus of spiders broadly called banana spiders because bananas are the plants on which these spiders are most often found. It's quite common for workers in other countries to discover these spiders in imported banana shipments.
A bite from the banana spider (also known as the Brazilian wandering spider) of Central and South American rain forests causes shortness of breath, excessive salivation, tremors and—for men—a persistent, intensely painful erection, known as priapism in the medical community.Where do banana spiders go? ›
As previously mentioned, banana spiders prefer warm regions. Consequently, they're often found throughout the Gulf states, from North Carolina to Texas. These arachnids thrive on high humidity and open space, making Florida a prime candidate for a banana spider habitat.What does a wandering spider look like? ›
The species vary in color, though all are hairy and mostly brown and gray, although some species have lightly colored spots on their abdomen. Many species have bands of black and yellow or white on the underside of the two front legs, according to the University of Florida (opens in new tab).Is a wandering spider poisonous? ›
They are highly defensive and venomous nocturnal hunters. Despite their notoriety for being dangerous, only a few members of Phoneutria have venom known to be hazardous to humans, but the venoms of this family are poorly known, so all larger ctenids should be treated with caution.Is spider poisonous in food? ›
Mushrooms are sometimes poisonous, but spiders are not; they are venomous (their toxins are proteins and work by being injected, not by being eaten). Second, we have a set of false assumptions about spider venoms. Almost all spiders are venomous; only two small families lack venom glands.Do spiders live in fruit? ›
Spiders and other arthropods have been accidentally hitching a ride in produce since it started being imported into the United States. Bunched fruits such as grapes and bananas make excellent hiding places for small insects and arachnids.