Cheshire

One of the cool things about being an entomology major is hearing stories about bugs. Generally, folks tend to notice spiders for whatever reason. I have no idea why people notice spiders over things like beetles or caterpillars. I think it’s because they like telling stories about encounters with large, potentially dangerous animals.

Spiders have a reputation for being dangerous. Even in the species which are known to pack a punch, this is probably undeserved. Great example: the brown recluse. Many horror stories abound from this spider; it’s notoriety means that bites are probably overdiagnosed. There’s even one site which specializes in showing pictures of unconfirmed ‘bites’ with no background information or no way to verify that these are, in fact brown recluse bites or something more mundane like a staph infection…or, say poison ivy. This one looks like Romana’s sign, a symptom of Chagas disease but could just as easily be an allergic reaction.*

I hear tons of stories about spiders all the time. One guy tried to convince me that a brown recluse had laid eggs in his leg and that they had hatched. I’ve kept brown recluses as pets and had to freeze an egg sac once (don’t want them running wild by accident…small slings are hard to handle). I didn’t need her to implant the sac in my leg, just spin it into the corner of her cage. They guard it for awhile, then the slings go off to find their own small, dark and quiet corner of the world.

Some of the most interesting stories I hear are about the size of the spiders we have here in Iowa. The largest spiders we have here in Iowa are probably our Dolomedes species. One I hear described very frequently is Dolomedes tenebrosus which can get up to about three inches or so. Usually when I hear them described, the person describing them puts their hands about a foot apart…about four times the legspan of these guys and about as big as the biggest spiders known to man.

The family these guys are from, Pisauridae, is actually pretty cool. They tend to be aquatic or riparian, and are rarely if ever found far from water. They keep to themselves, mostly and are completely harmless, although their size (two to three inch legspan) tends to give folks a shock.

The cool part is that this family exhibits a form of maternal care. The female carries the eggsac around in her mouth, and when the young’uns hatch she spins a web for them to hang out in for the first few instars. They seem to be very cordial to one another, balling up when blown on. I’ve never kept a sac myself so I don’t know if they’re cannibalistic.

Anyways…there’s a few urban legends busted for you.

*Just FYI: I’m not a doctor. The internet is not a substitute for trained professionals, no matter how many websites claim this privilege. Do NOT try to diagnose a spider bite from your friend who claims to know a lot about spiders and do NOT assume that festering wound is a spider bite unless you’ve captured the spider yourself and can have it ID’d by a trained professional. Extension entomologists are great for this.