Book Scorpions Are a Thing That Exists, & This Is Why You Should Like Them
If you were to flip open a book and find yourself facing what looks like a really tiny scorpion without a stinger traipsing around a page of the book, you might (quite understandably) scream bloody murder and a few choice bleep-worthy words that would make even a drunk sailor on shore leave blush.
^ Picture credited to Wikipedia user Fice at the Wikimedia Commons.
And you wouldn’t be entirely wrong to have such a reaction -- when it comes to scorpions, the smaller they are, the more dangerous they usually are (because the smaller they are the less they can rely on their pincers for protection and hunting, so the more potent their poison has to be).
Luckily, however, what you’ve encountered doesn’t have a stinger, so it’s not a true scorpion, but rather a pseudoscorpion. They’re arachnids like scorpions, but belong to an entirely different order (Pseudoscorpiones instead of Scorpiones).
It’s very likely you have some skipping around your house and don’t even know it, because when I say these little dudes are tiny I mean tiiiiny.
The biggest species we know of (which is found in Ascension Island) can grow to a whopping… 12 mm long. Most species range from around 2-8 mm.
Like I said, they’re tiny.
Household pseudoscorpions are found all over the house, but are most famously found inside books, which has earned them the nickname of “book scorpions”. ‘Cause, y’know, they’re in books and look like scorpions.
If you do come across a book scorpion, don’t kill it.
We bookworms are fans of the book scorpion.
...Well, we metaphorical bookworms are fans of the book scorpion.
Literal bookworms are probably less enthused about having them as neighbours, seeing as they’re a favourite book scorpion snack (which, ironically, is the reason we metaphorical bookworms like pseudoscorpions so much -- they’re fantastic helpers for book conservation!).
To ramp up the irony even further, one of the reasons book scorpions aren’t true scorpions is that they breathe by way of spiracles rather than book lungs, (a kind of primitive lung; to learn a bit more about them and see what they look like, see the end of the post).
And even if you’re not a book lover, you still have reason to be a book scorpion fan; on top of eating bookworms they also enjoy om nom nomming other small parasites like mites, clothes moth larvae, and carpet beetle larvae, so even if you find one far away from your books they’re definitely worth keeping around.
Think of it like this: It’s impossible to have an insect-free and/or arachnid-free house, And if you have to live with uninvited housemates, you might as well make friends with the ones that pitch in with the housework and offer a free cleaning service.
These little guys are pretty neat, and the more info I read on them the more neat tidbits I find that I think might interest people, so I’ll end this post here and write another with more facts on book scorpions sometime in the near future.
Spiracles are little holes on the exoskeleton of some bugs that lead to a windpipe that supplies oxygen directly to the animal’s tissues through a system of tubes much like how our arteries would.
^ Both the images were taken from this blog post by Dragonfly Woman (aka Chris Goforth, Head of Citizen Science at North Carolina Museum of Natural Sciences & @DragonflyWoman2 on Twitter) about how insects breathe, which explains how spiracles work in a very approachable manner.
If you’re confused about how they work or want to learn more, it’s definitely worth a read.
Book lungs are a kind of primitive lung that got its name from the fact that they’re made up of hundreds of thin layers of tissue that absorb oxygen into the scorpion equivalent of blood, which look a lot like pages in a closed book:
^ The images are screenshots from Episode 1 of BBC’s 2005 docuseries Walking With Monsters: Life Before the Dinosaurs and are technically brontoscorpio lungs, not a scorpion’s.
But I couldn’t find any images quite as good as the ones I knew I could find on that episode (because I’m a total fangirl for the entire Walking With franchise), and since scorpions (like most arachnids) have changed incredibly little of their physiology when compared to their ancient ancestors, this is a close enough approximation.
If you want to see the scene where they show how the lungs work, I know Canadian Netflix has the entire Walking With franchise (since content availability on Netflix varies by country, I can’t guarantee about any other countries).
