Several animals like cellar spiders and harvestmen fall into the "Daddy Longlegs" category. Depending on where you live, the term may mean something different, which can be confusing. But are these species spiders?
The answer to this question is “it depends”. The only daddy-longlegs that is, indeed, a spider is the cellar spider. Harvestmen are arachnids (but not spiders) and crane flies are, well, flies and, as such, insects.
But what’s the origin of this confusion? How can some daddy longlegs be arachnids but not spiders? Are they as poisonous as people say they are? We will answer those questions and much more below.
Spiders are arachnids belonging to the Araneae order. They are cold-blooded invertebrate creatures with two body segments and eight legs.
All spiders produce venom to a degree, and they use their fangs to inject their poison into their prey.
Likewise, all spiders can spin silk from their abdomen. Some species can make intricate webs to help them catch prey.
Except for very few exceptions, spiders are carnivores. Thus, these animals feed on insects, larvae and other spiders. Larger species can also feed on lizards, amphibians, rodents and birds.
Most spiders have four sets of eyes, but there are a few species with fewer.
This question is very complex to answer. After all, different people in different areas call different animals “longlegs”.
So, we have compiled a list with the different invertebrates known as daddy-longlegs. On the list, you'll find some information about these species and whether they are spiders or not.
The most popular longlegs may be the invertebrates belonging to the Opiliones order.
The Opiliones order contains over 6,000 different species. Although they tend to live in tropical environments, you can find them all over the world.
Harvestmen come in different sizes and vary from 0.6 to 23 mm (0.02 to 0.9 inches). Their legs are several times longer than their bodies.
These eight-legged critters are arachnids, but not spiders. You can compare this to how lions are felines, but they’re not tigers.
You see, the Arachnida is a class of invertebrates. This class includes orders like spiders, scorpions, mites, ticks, solifugae, and harvestmen.
So, yes, harvestmen relate to spiders, but these fellows are closer to mites or scorpions.
Because they have eight legs, it is not hard to see why harvestmen are mistaken for spiders.
Another trait that harvestmen and spiders share is that they prey on invertebrates. So, both eat small animals like aphids, flies and mites.
The main difference between Opiliones and Araneae is that they can't produce silk. Thus, Opiliones can't spin webs either.
Opiliones also lack venom and have different respiratory systems to spiders.
Opiliones also have a more varied diet than their only carnivore cousins. Besides invertebrates, larvae and molluscs, harvestmen can eat vegetable matter, too. These animals even feed on feces. Yikes!
But the most impressive behavior among these animals may be their defense mechanism.
Harvestmen like to cluster together by the thousands in small caves and creases. These creatures create a shapeless dark mass of outwards legs. This vision kind of look like a giant fluffy animal sleeping… until you poke it.
But that's not all. These species can release a peculiar, ammonia-smelling fluid to deter predators. This scent is useful, considering that these animals don't have any poison.
In short, no, they are not dangerous to humans at all. In fact, harvestmen are some of the most harmless arachnids out there.
Like we have mentioned before, harvestmen can’t produce poison as they lack venom glands.
But even if they were venomous, they have short fangs that cannot pierce through human skin.
Because they feed on harmful insects, harvestmen are beneficial in crops and gardens.
The only real nuisance about these guys is: they tend to form large, foul-smelling colonies.
Cellar spiders belong to the Pholcidae family.
The Pholcidae family contains over 1,800 species in all continents except Antarctica.
In the wild, these carnivore arachnids live in tropical and subtropical regions. That said, these animals adapted to live in human dwellings around the world.
You can find these creatures living in basements, attics and dark corners of houses.
Cellar spiders live in our houses and prey on harmful insects like mosquitoes and flies. So, these animals are beneficial (although sometimes feared) creatures to have around.
These spiders are small in size (2–10 mm / 0.08–0.39 inch) and have very long legs that can reach four to five times the body's length.
Like all members of the Araneae order, cellar spiders are venomous and produce silk. They spin webs to catch prey.
A cellar spider spins its silk in the shape of an irregular web. These webs have no sticky filaments.
But, when an insect stumbles upon the web, the vibration alerts the spider that dinner is ready.
Contrary to most spiders who are loners, cellar spiders tend to build their homes close to each other. So, it’s not uncommon to find several of these guys hanging around in our homes.
Yes, and their venom is much more potent than a Black Widow's poison.
Nah, we’re joking! But weirdly enough, that urban myth does exist.
Legend has it that a cellar spider’s venom is so potent that it could kill an adult human fast. Cellar spider bites are not lethal because their fangs are so short that they can’t penetrate our skin.
Like most urban legends out there, there is a small slice of truth in this one. A tiny, tiny fact.
A cellar spider’s fangs are about 0.25 mm long, and the average human skin thickness ranges from 0.5mm to 4mm. Although they can pierce the skin, it’s not enough to harm us.
Additionally, cellar spider venom is not by any means strong enough to hurt a human being, let alone kill one.
In 2004, Discovery Channel's show MythBusters tested the daddy-long-legs venom theory. The research found that cellar spiders can puncture the skin. Yet, the bite produces a mild, short-lived burning sensation.
But there's more confusion surrounding the true scope of the term “daddy-long-legs." Some people in Canada, the US and Britain also use this expression to refer to crane flies.
Why? Well, because as you might have guessed, crane flies also have long legs.
"Crane flies" is also a blanket term used for members of the Tipulidae family. This large family includes some 15,000 species.
Like harvestmen and cellar spiders, most Tipulidae species live in the tropics. But you can also find these animals in colder latitudes, hanging around bodies of water.
But unlike other types of daddy-long-legs, which are arachnids, crane flies are insects.
These winged insects are morphologically like mosquitoes. So, these insects go through a complete metamorphosis during their lives.
Thus, crane flies go through egg, larval, pupal, and adult phases.
Crane flies lead short and sad lives. With a lifespan of approximately two weeks, most adult crane flies don't even feed. Why? Because the mouths of these insects cannot eat.
Crane flies are not dangerous to humans.
Despite looking like giant mosquitoes, crane flies don’t bite or sting.
Crane flies live long enough to reproduce, and that’s about it.
Even though their existence may seem pointless, they play a part in their ecosystems.
For starters, crane fly larvae help increase bacterial production. So, these insects are helpful to the ponds and bodies of water where they develop.
Secondly, they're essential food sources for other animals. Amphibians, small reptiles, spiders, and other insects all eat crane flies.
But crane flies are different from other invertebrates with which they share a nickname in a big way. People consider these insects a pest.
These flies eat vegetable matter and roots as larvae. So, these animals end up stunting the growth and sometimes killing the plant they consume.
Unlike popular belief, crane flies don't eat mosquitoes. As adults, these insects can’t kill or consume any insect. So, their “mosquito hawks” nickname is nos accurate.