Why the Venomous Daddy Long Legs Can’t Bite Humans

What is the mysterious ‘Daddy Long Legs’? An insect, a flower or some kind of animal with big teeth? Why are they so famous? Are they venomous? Why can’t they bite humans? Many questions may arise in one’s mind after reading this article’s title.

Actually, a Daddy Long Legs is among the most common house spiders around. What is reason they cannot bite us and inject their venom into us while they’re wandering around freely? Let us do some more research about this tiny creature.

Spider with cubs

Daddy Long Legs or Granddaddy Long Legs are a common spider species that are distributed worldwide. Scientifically known as Pholcus phalangioides, they can easily be found anywhere inside the house or in the backyard and under logs or rocks. Other suitable places for them are cellars, buildings and caves. They prefer to live in dark and damp areas, and they are often confused with Opiliones, or Harvestmen, which share the same name but are basically eight-legged arthropods, not spiders.

Image: Olei

Why they can’t bite?

Like any other spider, these fragile-looking creatures have fangs to puncture the skin of other animals, like humans, they might bite. They are also very famous for being venomous. So, what’s stopping them from biting us? To understand this, we must learn about their body structure. Interestingly, these spiders have very long legs, attached to a small body. They are also equipped with venom glands and fangs. But sadly (for them), these fangs are too short, about 0.25 mm, to penetrate human skin, which is generally about 0.4-0.5 mm thick.

In arachnological terms, these fangs are called ‘uncate’ and are fused at the bottom of their body, making it difficult to open their jaws wide enough to bite. This is the reason they are not considered as dangerous to humans, as they can’t bite.


Image: Bob

Are they truly venomous?

It’s a legend that they are deadly spiders – these claims are a myth and completely baseless. Their lethality on mammals has not been studied at all, due to a variety of reasons. Though their bite may lead to a mild burning sensation, that’s not harmful. Also, there is no scientific evidence that can prove it.

Image: Sublimat


An interesting possibility

There is a possibility of proving that these tiny spiders are venomous. It is their diet. They often kill and eat other deadly spiders, including the redback spider, which is well-known for its venom. This could be the origin of such rumors. Yet even if they are poisonous, either their venom is weak or practically harmless.

So, don’t be afraid of the ‘daddies’ next time you see them around. These cute little critters are totally harmless.

Sources: 1, 2, 3