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

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).

Re: woodlouse spider

[ex-wellread.livejournal.com]

Well, I hope they don't like the Denver area! I think I might faint if I saw one of those. Believe me, I will not be looking for them!

Re: woodlouse spider

[(Anonymous)]

I just found one of these on our screen door. I had no idea what kind it was or if it might be venomous....glad to learn that it's not. I live in Aurora, CO....ugg..that spider gave me the willies!