365 Urban Species. #098: Woodlouse Spider

[urbpan]

Urban species #098: Woodlouse spider Dysdera crocata

While handling this spider trying (unsuccessfully) to get a better photograph, I became unnerved when I noticed its fangs. Usually on a spider this size (maybe 3/4 or an inch, or a little less than 2 cm) the fangs are inconspicuous, tucked away underneath. The woodlouse spider has long, obvious fangs, presumably strong and sharp for piercing the shell of their crustacean prey. Most spiders' fangs are not strong enough to bite through human skin, but some are, and this individual looked capable. But it showed no inclination to bite, instead clambering in a panic to remove itself from the light.

Research after the fact indicates that it indeed could have bitten me, but it wouldn't have injured me seriously. Or to use some delicious technical language: "D. crocata bites have been implicated in causing a localized, intensely pruritic rash with coalescing dermal papules 4-5 mm in diameter.  The bites apparently do not result in any systemic neurotoxicity or cytotoxicity." (http://www.ento.psu.edu/extension/factsheets/Spider/spiders.htm)

The woodlouse spider, unsurprisingly, is found anywhere woodlice are. Under logs and stones and other debris near buildings is where you will most likely encounter one. They were apparently introduced to North America and Australia, along with their favored prey, from Europe. It's possible that no introduced woodlice are considered invasive because their predator comes along with them when they travel.

Comments

[rinalia.livejournal.com]

I like the spider's coloring.

He (or she) has a cherry for a head and a pigeon's egg for a butt. And legs - those too. :)

[ankhanu.livejournal.com]

I've never seen one of these; I'm going to have to be more observant. Man those fangs are imposing.

[harebell.livejournal.com]

Interesting. I'm pretty sure those are the ones I see when I do any gardening.
I've never seen them until moving down here.

[artemii.livejournal.com]

how common are these in our area?

[urbpan.livejournal.com]

I can't seem to determine this. I personally have found three over the past few years. I'd guess: "Less common than jumping spiders Phiddipus audax and cellar spiders , but more common than black widows and brown recluse spiders (neither of which I've ever seen in New England (yet?))

[ex-wellread.livejournal.com]

In general, spiders, snakes and most incests don't scare me. But anything with fangs like that does give me the willies. We have enough spiders to worry about out here in Colorado so I hope that isn't another.

woodlouse spider

[(Anonymous)]

Well man, dont give your hopes up, I live here in southern colorado and I see these spiders very often. I used to think they were brown recluses but further study denied my theory. But I'd say in the past year from summer 2005 to today (2006) I've spotted at least 10 of them, but then again I am very interrested in this particular spider and I do go out and acually make an effort to look for them. Look under logs, tarps that have been left on the ground for a long while, bricks (or stones) carpet that's been left outside for a long while etc. Anywhere that may look like it could be cool in temperature under the object may hold a Louse Spider (Dysdera Crocata).

[(Anonymous)]

Thanks for the info. We found one in our garden shed in London UK which has totally blown my oft-repeated theory that I used to put to my kids that there are no poisonous spiders here in the UK. It was a creepy, unusual looking thing, and has put the kids off spiders in a big way but it is proving partially reassuring to find that there are no systemic effects.

i hate these!!!

[(Anonymous)]

i live in souther california and my house is coverd in these things. during the day u can see them under rocks and in corners out in my shed but as soon as the sun starts to go down i see them every where infact i just saw one tonight crawl across my wall not 2 feet away from my head! they get to be about the size of the tip of my index finger to the first nuckle which is huge when its comming right at you!

Re: i hate these!!!

[(Anonymous)]

as a kid i conducted spider and insect wars of almost every sort, pitting them against one another. far and away, these were the nastiest spiders.

although i've seen a few internet posts to the contrary, we always found these spiders to be extremely aggressive, and quite creepy. the fangs are gigantic.

WOODLOUSE SPIDER

[(Anonymous)]

THESE ARE AGGRESSIVE SPIDERS I LIVE IN WALES,U.K. AND THERE ARE LOADS OF THESE IN OUR BACKGARDEN, THEY HAVE MASSIVE FANGS AND MY BROTHER ACTUALLY GOT BITTEN BY ONE OF THESE THINGS AND IT HURT ALOT, NO SIDE EFFECTS THOUGH...

I have one with me now

[spaceballsthelj.livejournal.com]

My girlfriend and I were watching TV, and she noticed one of these guys on the wall. We live in Northern Los Angeles, CA. He was walking on the wall above our shelf and I put a zip lock bag below him, and he jumped in like he owned the bag. I zipped him in there, and looked him up. We are constantly encountering different types of spiders in our apartment, and this was a new one to me. Good to know he's not venomous, but I wouldn't want to get bit by those monstrosities we call fangs. I'm going to let him go free outside so he can eat other creatures, and not bite me in my sleep.

[(Anonymous)]

I live in Pittsburgh, PA and my sister who is extremely scared of spiders started flipping out and told me to kill the spider she had found. Since it was red and I had never seen anything like it, i looked it up. At least it wasn't venomous.

weird spider bite.

[(Anonymous)]

i was bitten one night by this reddish brown spider. it hurt like heck. so when bitten i did some research on the almost dead spider. to see what bit me.over the next two days i had a high fever and could not keep any food down.come to find out from my science teach that the spider was a woodlouse spider and found nothing on them being harmful to humans. just thought this would be nice to know that they are in my way and i did not have an allergic reaction to it either. according to my doctor.

Nasty!

[(Anonymous)]

These spiders infested my basement for two years. I was so freaked out by them. Now that I got rid of them I noticed a pill bug in my basement. Oh god.... There back....

-Dr. David Wolf

Woodlous Spider

[(Anonymous)]

I get loads of these in my house here in England-varying colours from blood red and pinky-pearl to purple and mauve to brown and grey.

I've currently got a large brown/grey specimen crawling around a glass where I trapped it-its got nasty big black fangs :s

They can be agressive but most of the time they are eager to run away when they encounter people.

They are very agile and be a pain to catch.

But the thing about them that really freaks me out is the way they wait outside my window until I eventually open it and then they jump inside as soon as it does!

They are too clever.....


I had a bit of an odd encounter with a blood-red female the other day when I went into the downstairs bathroom and suddenly felt a small weight on my hand-I turn on the light to see it hunched up between my knuckles!

It soon realised that perhaps its choice of hiding place was unwise and so it squirted some browny-white stuff (spider poo lol?) on my hand before I flicked it away.

I don't like these spiders which is why I'm glad I've got a nice population of daddy-long-legs spiders that occasionally snare one or two of these for their supper!

WOODLOUSE!!

[(Anonymous)]

I live in So Cal...so i just got bit by one of these tonight and was online looking for what it could have been. At first i thought it was a brown recluse and got terrified. it pinched the bottom of my foot and hurt bad. it started itching and then slightly burning but only lasted less than an hour. i soaked my foot in hot water for about 5 min. and then put ice on it. it has been over 3 hours and i feel fine and the pain has gone away. there is no apperance of the bite/pinch. hope this helps anyone who got bit and is freaked out as much as i was. From what ive checked i don't think these are very harmful. just watch where your stepping. :)

Woodlouse Spider

[(Anonymous)]

whew, glad I found this message board because I was ready to MOVE!
The guest house I live in is only inches away from a told old wooden fence which is right next to some kind of old crappy gazeebo that my white trash neighbors have, so I think I've figured out why I found 2 of these things in my house (one dead, one alive). Most likely they're around because of all the old wood close by. The one that was alive was moving accross my wall. I approached it thinking that from a distance it was just a normal house spider. When I got closer and saw the size of it and the white tail end I got spooked, grabbed a nearby bug spray and hosed it down quickly while I looked around for something to smash it with. It seemed to move somewhat slowly, maybe because it was weighed down after I sprayed it, but I agree that it didn't seem very aggressive, it just tried to turn the other way and walk away from me. Well, anyways, I'm just relieved that it's apparently not too venomous, though Wikipedia says that their venom can be fatal without medical attention. I'll have to find a few more sources on that before I feel TOO safe.

Woodlouse Spider part 2

[(Anonymous)]

btw, I'm in Northern California
and like one of the other comments above, I too originally mistook this spider for a brown recluse (violin spider)

*sigh*

[(Anonymous)]

that makes me feel a lot better. My sister and I were weeding in my back yard and we found one like that and she picked it up and she through it on the ground and we ran into the house and researched it. thank you for this wonderful info.

[(Anonymous)]

I saw one this summer in Charlotte, NC. Never saw one before and was very interested in them. Haven't seen any since.

freaked out

[(Anonymous)]

I just found one of those in my room no more than 3 min. ago. I was getting ready to go to sleep and I saw it run across my floor. It really freaks me out because my room is in the basement of my house and I dont know if there are more of them or not.

Woodlouse Spider

[(Anonymous)]

When we moved into our house we were over run with these spider's they seemed to be everywhere we killed Lot's of them by jumping on them, we don't see any now, But if we do we still jump on them! We were told they can be dangerous to young children by the insect department of the museum of wales in Cardiff

PLEASE HELP!

[(Anonymous)]

Hi, i was hoping somebody here would be able to help me. I just spotted i bright red spider running accross the bathroom door, and then onto the floor. I paniced and immediately stamped on it. Having looked about on the internet it looks like the woodlouse spider is the closest description to what i saw - I've also recently saw the odd woodlouse in the bathroom, so this would make sense. I have a 4 month old baby living in the house, and am now worried about her safety. Is there likely to be more of these spiders? Is there a way to get rid of them, and will my daughter be safe? Thanks in advance for any help :)

Re: PLEASE HELP!

[urbpan.livejournal.com]

Some people who are worried about spiders such as black widows have regular visits by exterminators. The woodlouse spider isn't as dangerous, but if you are that concerned, that's what you could do.

The woodlice are attracted to the rotting wood in the bathroom, so getting rid of them requires kind of a big carpentry job.

Found of these in Britain

[(Anonymous)]

all my life never seen one of these, so thought with its big fangs might be a stow away from a holiday, however nice to know its native, but the one i found was an inch and a half so im guessing these little critters grow bigger with enough food.

glad to have found this site

[(Anonymous)]

last summer 2007, i had a ton of these in my basement. forgot about them until yesterday - april 18 08. i am landscaping my backyard and moved a ton of rock - i think we found about 7 of them. they are creepy.

Re: glad to have found this site

[(Anonymous)]

forgot to mention, i am in denver, colorado.

Woodlouse Spider

[(Anonymous)]

I've got those in my bathroom!

I bought a damp old house in 2004 and realise over time that the woodlice were disappearing. I thought that was me - keeping the house warm and clean and making the woodlice unwelcome.

Until.... I went downstairs to use the bathroom one night and switched the light on. Jeeeeeeepers!

I don't know who was the more scared. If you include the legs it spans approx 35 - 40mm, has HUGE fangs and can rocket to the gap under my bath in split seconds.

Occasionally, I've seen little orange baby spiders as well so I know it's not a one off.

Thanks to a weird immune system and a couple of large and lairy wolf spiders, I've got to be wary of being bitten by spiders.

I don't know which is worse - knowing my house is damp and dark enought for these guys to take up permanent residence (albeit doing a good job) or knowing that I'm hostess to one of the few spiders in Britain that could do me serious harm if it bit me.

Still, over four and a half years I've only spotted an adult twice - so I think I'm safe!

woodlouse spider

[(Anonymous)]

Live in a basement apartment in Massachusetts... saw one in my bathroom. Definite sighting, looks just like all the pictures. Noticed the peculiar red color first, and then upon closer inspection (reflexes got the better of me, sorry bug lovers) the fangs were obviously visible. Neat find. Or it least it was.