Frequently Asked Questions
Paula E. Cushing, Ph.D., Curator of Invertebrate Zoology, Denver Museum of Nature & Science
Question: Is it true that daddy longlegs are the most venomous spider, but their fangs are too small to pierce human skin?
Answer: This is absolutely not true! Daddy longlegs are not spiders and do not have fangs or venom. In the United States, the name “daddy longlegs” is usually used in reference to an arachnid in the Order Opiliones. These long legged animals are found in dark, damp places. In Europe they are sometimes referred to as harvestmen because people most often notice them during harvest time in the newly cut fields. Although they sometimes prey on insects, they are primarily scavengers, feeding on different kinds of organic material.
One family of spiders, the Pholcidae, also sometimes goes by the name daddy longlegs spider. However, there is no evidence to support the myth that this real spider has venom which is particularly harmful to humans. You can get more detailed information about this myth at:
http://spiders.ucr.edu/daddylonglegs.html
Question: Are brown recluse spiders the most dangerous spider to humans?
Answer: No. Brown recluse spiders are in the family Sicariidae and in the genus Loxosceles. Although their venom can cause medical problems (ulcerating wounds) in humans, recluse spiders are not found throughout the world and there are many other medical conditions besides spider bites that can cause ulcerating wounds. In regions were recluse spiders are not found, it is very important to eliminate those other medical conditions before blaming a spider!
Some of these medical conditions that have been misdiagnosed as spider (particularly recluse spider) bites that can cause dermonecrotic injuries are listed at the following website:
https://spiders.ucr.edu/causes-necrotic-wounds-other-brs-bites
The brown recluse is the common name for the species, Loxosceles reclusa. All species in the genus Loxosceles have venom that can cause necrotic lesions in humans because the venom includes a protein called Sphingomyelinase D and that protein breaks down the Sphingomyelin that is found in the cell walls of the tissue surrounding the bite site. However, as with the majority of spiders, brown recluse spiders bite humans only when seriously provoked.
You can get much more information about the recluse spiders from the following website:
http://dermatology.cdlib.org/DOJvol5num2/special/recluse.html
One of the most dangerous species of spiders for humans is the Sydney funnel web spider, Atrax robustus. This robust spider is found in Australia. These spiders can be quite aggressive and the neurotoxic venom can kill a human.
Question: Is it true that the black widow spider always eats her mate?
Answer: Nope. Black widow females are no more likely than any other female spider to eat their mates. If the female is ready to mate and if the male sings the right sweet silk song to her, then she will allow him to approach and to mate. If the female is not particularly hungry, she will likely allow the male to leave unscathed after copulation. However, the female black widow, as is common in spiders, is larger than the male. Thus, if she is hungry, she may feed on the male but this is true of many species of spiders.
That said, there are populations of widow spiders in Australia where the male sacrifices himself to the female during copulation. Arachnologist Dr. Maydianne Andrade has done a lot of research on this phenomenon. Her website is well worth visiting! https://www.utsc.utoronto.ca/labs/andrade/
Question: My friend sent me an e-mail about a really dangerous spider that lives under toilet seats that can kill you if it bites you. Is this for real?
Answer: Can you say “gullible”? Didn’t your mother tell you not to believe everything you read? See the following website for information on this internet hoax:
https://www.snopes.com/fact-check/two-striped-telamonia-spider/
Arachnologist, Rick Vetter and his colleague, P. Kirk Visscher, traced the hoax to its originator and published an entertaining article about the hoax and how quickly it spread across the net in the Winter 2000 issue of the magazine American Entomologist, published by the Entomological Society of America:
https://academic.oup.com/ae/article/46/4/221/2474650?searchresult=1
Question: Why do spiders bite me at night?
Answer: Well, they don’t. If you wake up with a series of “bites” on your arm, leg, neck and you are certain that you do not have a vampire sleeping with you, then before blaming the poor spiders, check your bedclothes for bedbugs. Bedbugs are not a myth. They are flat, secretive insects that hide in cracks and crevices during the day and come out at night to suck your blood. The mysterious bites on your body are far more likely to be caused by mosquitoes, biting flies, bedbugs, lice, or your pet’s fleas than by spiders. So stop blaming our friends!!
Question: Is it true that we will inevitably swallow (some # of) spiders in our lifetime?
Answer: What do you think? No, this is not true. (Remember what we said about being gullible?)
Question: How many venomous spiders are there on Earth?
Answer: Nearly every spider you see is “venomous” because nearly every species of spider on earth has fangs and venom. What you really meant to ask was how many species of spiders in Colorado have venom harmful to humans. There are over 48,000 described species of spiders on earth and this number is increasing every year (see the World Spider Catalog for current numbers: https://wsc.nmbe.ch/). Of tens of thousands of species only a mere handful have venom of concern to humans.
Question: What should I do if I get bitten by a spider?
Answer: If you are ever bitten by an arthropod (insect or spider) or stung by an arthropod such as a bee or an ant and begin to experience unpleasant symptoms, you should go see your doctor. But do not go alone. Take the six or eight-legged suspect with you, even if the culprit is, by that time, dried up or squashed. It is nearly impossible to administer an effective treatment against symptoms caused by an arthropod sting or bite unless 1) it can be verified that the wound or symptoms were, indeed caused by an arthropod and 2) the arthropod can be identified. The treatment for a black widow bite (antivenin or serious pain killers) is going to be quite a bit different than the treatment for a jumping spider bite (aspirin and glass of water and maybe a tranquilizer because you are so paranoid about a little itty bitty spider).
If you have general questions about arachnids that are not answered via our website resources, you can contact Dr. Jerry Rovner at jsrovner@~@gmail.com. See Ask a question for more details.