Can you identify this spider?

August 8, 2007 6:56 AM

Can you identify this spider? It is currently in the basement of a house in upstate NY (Rochester area).

There's some concern among the homeowners (friends of mine) that it's a black widow.

posted by chr1sb0y to science & nature (22 comments total)

How big is it? It looks like it's an American House Spider which would be completely harmless.
posted by cardboard at 6:59 AM on August 8, 2007

The positive identification for a black widow would be a red, hourglass-shaped mark on the underside of the abdomen, but I assume nobody wants to get close enough to look. How big is the spider? Can you photograph it with a coin or common object for a sense of scale?
posted by Faint of Butt at 7:00 AM on August 8, 2007

Unless something's up with your camera (or my eyes), I'm gonna go out on a limb and say it's not a black widow, as the spider is red. A black widow spider looks like this.
posted by kittens for breakfast at 7:01 AM on August 8, 2007

Black widows are .. .. black, with a red hourglass on the underside of the abdomen.
posted by SpecialK at 7:01 AM on August 8, 2007

Well...It might be a male Black Widow...
Quoting Wikipedia:

Male black widow spiders are half the size of the female or smaller. They have longer legs and a smaller abdomen in relation to their body size. They are also usually dark brown with varying colors of stripes/dots, with no hourglass mark.

posted by Thorzdad at 7:09 AM on August 8, 2007

Male Black Widows (and cobweb weavers in general) don't have a fat abdomen like the spider in the picture.
posted by cardboard at 7:12 AM on August 8, 2007

It doesn't seem to have a match on the handy dangerous spider chart.
posted by mikepop at 7:30 AM on August 8, 2007

Male Black Widows (and cobweb weavers in general) don't have a fat abdomen like the spider in the picture.
And yet, the spider in the photo has both a fat abdomen and is on a web...

Could it be a "False Widow" (Steatoda grossa)?
posted by solotoro at 7:34 AM on August 8, 2007

Can you describe the web? It didn't come through very well on the photos. Is it circular and geometric, haphazard, etc.? In the third it looks a bit octagonal and geometric. I believe that eliminates Black Widows since they create webs with no pattern. Same thing for Steatoada.
posted by jwells at 7:39 AM on August 8, 2007

My bad, cardboard, on re-reading I realize you could well have meant male cobweb weavers, in general, don't have fat abdomens; apologies.
(PS - I don't know anything about spiders. I'm surprised how much I've enjoyed the two recent ID questions about them considering how little I like them in person.)
posted by solotoro at 7:46 AM on August 8, 2007

Man, I know this isn't necessarily the right thing to say, but the only identification I'd be doing on that spider would be with a shoe. A big ass shoe. Or a plank of wood. Or a book. I would identify it post-act as "Dead brain-eating spider".
posted by fredoliveira at 7:53 AM on August 8, 2007 [4 favorites]

Actually, black widows aren't always dark and black. I found one in California (LA) that was mainly brown, complete with red hourglass. (bloody thing fell out of my TV guide, on the sofa!).

I feel sorry for spiders. They get killed for no better reason than being creepy.
posted by Goofyy at 8:11 AM on August 8, 2007

Looks like a Brown Widow to me. Do a Google image search for "Brown Widow."
posted by HotPatatta at 8:19 AM on August 8, 2007

This is somewhat off-topic, but... why, on that dangerous spider chart, does the picture of the huntsman spider wiggle every five seconds or so? Is it just to freak out the spider-phobic? Is it some kind of issue with the gif, or with my browser (Firefox 2.0.0.6)? _{Is it just an imagining of my fevered subconscious?} Or do huntsman spiders periodically wiggle in real life, whereas all other species stand stock still with all their legs spread out for easy identification?
posted by Drexen at 8:35 AM on August 8, 2007 [1 favorite]

It should be noted that there is a whole family of 'widow spiders' beyond the dreaded black widow. It did kind of look like it had an hourglass on its underside and besides the colour it reminds me a lot of a black widow. I say let it outside or kill it and be done with it, and don't unnecessarily freak out unless you see more.
posted by dino terror at 8:44 AM on August 8, 2007

I second the brown widow proposal. I also second the shoe first, identification later proposal.
posted by littlegreenlights at 8:48 AM on August 8, 2007

Good on you for not getting crazy and killing it offhand, still my best guess is that is a black widow. The nesting habit is right... close to the ground on a hard man-made material. And the shape, gloss and markings are right. The only thing off is the color and I suspect the occasional black widow might end up that way.

I was bitten on the forearm by a black widow a couple of years ago, and all a got was a golf-ball sized purple lump that took a couple of weeks to disappear. Granted, I may not have been fully envenomated but it didn’t hurt and I suffered no other ill effects.

Just the same, I would kill it and destroy any egg sacks it had.
posted by Huplescat at 9:22 AM on August 8, 2007

The spider is of the Therid family- same as the Black Widow. It probably is on a tangle web- the typical web woven by spiders in this family. It is not a male- males are smaller and have structures called palps on the fifth set of appendages near the mouth.

It is no danger to you- these spiders do not wander- they stay in dark spaces and corners and they stay on their webs- the globular abdomen is awkward and not conducive to wandering around on floors, walls, etc....
posted by ohdeanna at 10:06 AM on August 8, 2007

I would suggest submitting it to What's that Bug? They're the best bug (and spider) identification site on the net.
posted by TungstenChef at 10:43 AM on August 8, 2007

Ok, I'm as positive as you can get looking at a picture over the internet that this is Steatoda grossa, the false black widow. See pictures here and here (1/4 of the way down) and especially here. Apparently the purplish-brown color is a dead giveaway.
posted by TungstenChef at 11:24 AM on August 8, 2007

Drexen, that's an animated .gif, not just your imagination. I think they're just being assholes.
posted by fidelity at 12:20 PM on August 8, 2007

It's Steatoda. They're often called "false black widows." The "red hourglass" on a black widow, by the way, may be orange or yellow and may not resemble an hourglass.
posted by Eothele at 3:39 PM on August 15, 2007