If you’ve ever watched Jurassic Park, then you should easily be able to recall the scene where Dennis Nedry is killed by the dilophosaurus. The dinosaur, first presumed to be harmless, unfurls its frightening frills before spitting acid into Nedry’s face. It’s an iconic sequence, so iconic that it might surprise you to know that dilophosauruses actually didn’t spit venom at all. It was made up for the movie (like so many other things were).
However, there are animals in real life that spit venom, just like the appropriately named: spitting spider.
Spitting Spider (Scytodes thoracica)
Spitting spiders possess the unique ability to “spit” a venomous silken substance from their chelicerae. While they still have silk glands in their abdomens, they also have silk glands located in their cephalothorax and are connected to the venom glands in their chelicerae. When they spot their prey, they measure the distance, usually a half an inch or so from them, before shooting the sticky, venomous, silk from their fangs. It covers the insect in a zig-zag pattern, as each fang produces a shot of the venom, and it congeals into a sticky net that keeps the insect on the ground long enough for the spider to immobilize it with a venomous bite. From there the usual spider procedure follows. They aren’t dangerous to humans, so you won’t need a can of Barbasol to protect you.
This entire process only takes about 1/700th of a second.
This spider also possesses other incredibly unique abilities and characteristics.
Originally this specific species of spitting spider has a palearctic distribution, but they have been introduced into the United States, New Zealand, and Australia. Spiders usually don’t function well in cold weather, and most of their species live in temperate weather, so it’s interesting how they’re originally distributed in colder climates. These spiders also have 6 eyes like recluse spiders. These eyes are positioned on their high, upwards-sloping carapace, which usually slopes downwards in most other spider species. Some species of spitting spiders exhibit prescoial behavior in which immature and mature spiders share a web with the intent of caring for spiderlings and eggs in a collaborative way. However, S.thoracia is an aggressive species that prefers solitude. Females will carry their eggs in pouches from their abdomen of chelicerae before they hatch. The spiderlings remain in their mother’s web until they reach sexual maturity and become solitary adults.
These spiders are incredibly unique, but while I’m debating getting another tattoo here in the next few weeks, I don’t think I’ll commit to this guy (yet). Until I do, I’ll think of them when I watch Jurassic Park.
Wow, I have to say every week I am simultaneously fascinated and horrified to learn of the many different types of spiders there are out in the world. Honestly, I think I’m starting to get used to them at this point which is a good thing when my mom yells for someone to get a spider out of the kitchen. I wonder what life would look like if spiders were the size of humans. Would they still be not as dangerous as we presume them to be or would they take revenge for all the cans of bug spray? Great use of your flairs this week, can’t wait for the next one!
This is the first time I have ever heard of spitting spiders, and now I have a new fear unlocked, they are pretty scary to look at (to me because I’m terrified of any kind of bug, spider, literally anything). However, it was cool to learn how some of the species can exhibit presciol behavior, like when the immature and mature spiders share a web. As usual, great blog post, I love your educational yet conversational writing style and I can’t wait to read next week’s blog post!