Myth bashing: Are daddy longlegs spiders?

Authored by zmescience.com and submitted by juicyvomit
image for Myth bashing: Are daddy longlegs spiders?

The answer is yes and no. It turns out that someone wasn’t very creative when naming little critters with long legs, and it can lead to a lot of confusion!

The critters most commonly referred to as daddy longlegs are not spiders. They are Opiliones and also known as harvestmen. They are also arachnids, but are more closely related to scorpions than to spiders. A few characteristics differentiate Opiliones from spiders. For starters, Opiliones just have two eyes. They cannot produce silk and therefore cannot make webs. They also lack venom glands. Spiders usually have two distinct body segments, but Opiliones have a compact oval-shaped body. It looks like one segment but the cephalothorax and abdomen are fused together so that the joint is hard to see.

Where it gets confusing is that there is also a spider called the daddy longlegs spider. They are also called cellar spiders. They are pale grey or tan and can have markings such as banding or chevron markings. Cellar spiders have typical spider features, like six or eight eyes and two distinct body segments. They produce silk and build a messy irregular web in corners. The threads are not sticky but used to alert the spider when prey has hit the web.

Are they the most venomous in the world?

There is a myth floating around that daddy longlegs are the most venomous spiders, but their fangs are too weak to bite a human. I have to admit that someone told me this years ago at summer camp (there were always dozens of them in the showers). However this statement is wrong for both daddy longlegs. The Opilione doesn’t even have any venom glands. The show Mythbusters took on this myth and found that black widow spider venom is much more toxic than the venom of the daddy longlegs spider. There aren’t any cases of this spider causing any harm to humans and no evidence that they are dangerous.

Crane flies are also colloquially referred to as daddy longlegs because, you guessed it, they have long legs. Even though they look like giant mosquitos, most of the adults live for such a short time (only to reproduce) that they don’t eat anything.

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All three of these daddy longlegs are found all over the world and are common in houses. Now you know what they really are!

IndigoRanger on December 16th, 2020 at 14:22 UTC »

They’re not completely harmless. One time I went camping with my family and my brother woke up because one crawled on his face. He was covered in them. We don’t know why they chose his tent to spend the night in, but there they were, hundreds of them. He screamed and tried to get out of the tent, but it was one of those 2-layer zip doors and he only got the first one unzipped, so he got stuck in between the tent layers and rolled the tent over on top of himself, which presumably freaked the spiders out, so they were scurrying every which way. Anyway, the spiders themselves didn’t do anything, but my brother had nightmares for years, and has a severe phobia of spiders now into his late 30s. Just wanted to share this story about my brother.

ReZpawner on December 16th, 2020 at 13:23 UTC »

"Harvestmen" sounds so fucking sinister.

ietsistoptimist on December 16th, 2020 at 12:19 UTC »

There are actually three different species that are referred to as daddy long legs, depending on where you’re from