"Daddy long legs are the most venomous spiders in the world, but their fangs are too small to bite humans."
You've probably heard this at some point. Maybe at school, maybe from a friend, maybe from that one uncle who has an opinion about everything. It's one of the most repeated "facts" in the world of pest control.
It's also completely wrong. Let's set the record straight.
The Myth: "Most Venomous Spider, Fangs Too Short"
This myth has been circulating for decades, and nobody knows exactly where it started. One theory is that it was a confusion with the brown recluse, which actually does have potent venom. Another is that it was simply made up and repeated so often that it became accepted as fact.
No scientific study has ever supported the claim that daddy long legs have the world's most potent venom. None. Zero. The MythBusters team even tested it in a well-known episode and confirmed that the myth has no basis in reality.
Are Daddy Long Legs Actually Spiders?
Here's where it gets interesting. Two completely different creatures share the name "daddy long legs," and this confusion is part of what keeps the myth alive.
Harvestmen (Opiliones) are the ones with the small, oval body and extremely long, thin legs. Despite looking spider-like, harvestmen are not spiders at all. They belong to a different order of arachnids. They have no venom glands, no fangs, and they don't produce silk. They physically cannot bite you.
Cellar spiders (Pholcidae) are actual spiders. They build loose, messy webs in basements, garages, and corners of rooms. They have the same long-legged appearance, which is why they share the common name. Cellar spiders do have fangs and do produce venom.
When most Nashville homeowners say "daddy long legs," they're usually talking about cellar spiders — the ones making webs in the basement and garage.
Can Daddy Long Legs (Cellar Spiders) Bite You?
Yes, cellar spiders can bite. But they rarely do, and when they do, it's not a big deal.
Cellar spider fangs are small, but they can penetrate human skin. Researchers have confirmed this through direct testing. The resulting bite feels like a very mild sting — less painful than a mosquito bite — and produces no lasting effects.
Their venom is not medically significant to humans. There are no documented cases of a cellar spider bite causing a serious reaction in any person, ever. You don't need to worry about cellar spider bites.
Can Harvestmen Bite?
No. Harvestmen have no fangs and no venom. They cannot bite at all.
What they do have are small pincer-like mouthparts that they use to eat decomposing plant material, small insects, and fungi. These mouthparts are not capable of breaking human skin.
Harvestmen are completely harmless. They're actually beneficial because they eat decaying material and help break down organic matter.
Are Daddy Long Legs Good to Have Around?
In many ways, yes. Both cellar spiders and harvestmen are beneficial to have near your home.
Cellar spiders are surprisingly effective predators. They eat other spiders — including brown recluse spiders. A cellar spider will actually invade a brown recluse's web, wrap it in silk, and eat it. They also eat mosquitoes, flies, and other nuisance insects.
Harvestmen eat decomposing material, small insects, and fungal spores. They're part of the natural cleanup crew in your yard.
For more facts about these creatures, check out our detailed guide to everything you need to know about daddy long legs.
When Daddy Long Legs Become a Problem
A few cellar spiders in the basement aren't worth worrying about. But when their numbers get out of hand, the webbing becomes unsightly.
Cellar spiders don't clean up their old webs. They just build new ones nearby. Over time, this creates thick layers of dusty webbing in corners, along ceilings, and around light fixtures. In basements and garages, heavy cellar spider activity can make a space look abandoned.
Harvestmen are known for forming large clusters on exterior walls, especially in fall. Dozens or even hundreds of harvestmen will gather together on shaded walls, under eaves, and around porch lights. While this behavior is harmless, most homeowners find it unsettling.
If you're dealing with large numbers of daddy long legs in your Nashville home, it usually means you also have a lot of other insects. Daddy long legs go where the food is, so a large population suggests a larger pest issue that's worth investigating.
How to Reduce Daddy Long Legs in Your Home
Since daddy long legs follow their food supply, the most effective approach is reducing the other insect populations in and around your home.
Address other insect problems first. If your basement has crickets, gnats, or other small insects, treating those will naturally reduce spider and harvestman populations.
Lower humidity in basements. A dehumidifier set to keep humidity below 50% makes the environment less attractive to both daddy long legs and the insects they eat.
Remove webs regularly. Knocking down cellar spider webs forces them to relocate. If you're consistent about it, they'll move to a less disruptive area.
Seal entry points. Gaps around windows, doors, and foundation penetrations give both daddy long legs and their prey easy access to your home.
If excessive spiders are a concern, Thrive provides spider removal across Nashville, Brentwood, Hendersonville, and all of Middle Tennessee. You can also learn about other common species in our guides to wolf spiders, common house spiders, and everything you need to know about spiders.
Frequently Asked Questions
Are daddy long legs the most poisonous spider?
No. This is a myth with no scientific support. Cellar spiders (one type of "daddy long legs") have mild venom that is not dangerous to humans. Harvestmen (the other type) have no venom at all.
Why do daddy long legs cluster together?
Harvestmen gather in groups for moisture conservation and predator protection. The cluster makes them appear larger, which may deter predators. These gatherings are most common in fall and are completely harmless.
Should I kill daddy long legs in my house?
In most cases, no. Daddy long legs are beneficial because they eat other pests, including spiders that are actually dangerous (like brown recluse). If their numbers are excessive or the webbing is bothersome, reducing their food supply and lowering humidity are better long-term solutions than killing individual spiders.
