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Sac Spider - Cheiracanthium mildei - female

Sac Spider - Cheiracanthium mildei - Female
Marblehead, Massachusetts, USA
May 19, 2002
Spider is mildly poisonous. Found indoors and out. In prime habitat ( dense leafy vegetation ) larger and greener hue from consumption of green larvae. Grows to 0.5 inch. This individual was captured in backyard shrub.
Does not bite humans even when provoked. I welcome this spider indoors.

Biting Humans
I know this is quite old but... I have been bitten by this spider (I live in Massachusetts too) more than once, on three occasions I caught the spider biting me (always at night, always on my bed, it is by an open window in the summer months). I actually get very ill when bitten by these spiders, and I just got bitten, and caught her yesterday. I am very ill at the moment. That is how I found your site actually. I hold no ill will toward these little creatures, but some people can get quite sick from their bites (nausea, muscle soreness, headaches, or for me head heaviness, dizziness, and a sore throat). Once bitten, for me anyways, I get a small lump, it gets bigger within a day and very red, I start to feel tired, and then the general symptoms listed above start, after three days I start to feel better, but it takes me a whole week to fully recover, this has happened to me every time, and in the span of three years. When I was younger I had no reaction from them, now I feel like death. I have to go lay down now, but remember, no one is a complete authority on everything, everyone reacts differently to different things, even spiders for that matter. By the way, this is a very serious comment, I just feel a bit strange and loopy, so it may sound like a joke, but it's not, sorry.

Bites Humans
I disagree with your comment about this spider biting humans, I in fact have been bitten by this very species.

Sac Spider - Cheiracanthium mildei
Perhaps this particular species of Cheiracanthium doesn't bite humans but the Cheiracanthium Miturgidae definitely does and as they are related, I think I would be extremely careful around this spider. I would like to direct you to a website that shows the possibility of this spider biting humans.
If you look up finding spiders by location and then click on Retreat (as in the place you find them, in a retreat, by day) and then click on the Cheiracanthium Miturgidae you will see an almost identical spider to what is listed on this site. The Miturgidae doesn't have the cross on its abdomen or the recessed area on the thorax but other than that it is extremely similar in appearance yet poisonous, like the brown recluse. The places these people have bites, I would say that the spider's weren't provoked much. Perhaps the ankle bite victim walked too close and the hand bite may have accidentally brushed one. The point is, they are apparently aggressive and will bite leaving quite a lesion. I live in California and found one in my apple tree. It has a worldwide distribution so I wouldn't go picking up one of these beasts.

Name mix-up
I believe you are confusing this spiders Family, Genus, and species names. Miturgidae is actually a fairly new FAMILY name given to this group of spiders known as "prowling spiders" of which the genus Cheiracanthium and species mildei now belong to.

These spiders are also known as wandering or hunting spiders. They also are known by some different common names, such as, "Long-legged sac spider", "Black-footed spider"

I haven't visited the site yet but I can tell you that I have handle the female of species shown, and it is not prone to biting. I did however conduct an experiment with a medium size female. The spider was resting on the top-side of my hand. I commenced blowing on it. After a while, it dug it's fangs into me, as if to anchor itself. The sensation was a stinging. I then blew very hard and the spider became dislodged and was sent air-borne. The small reddish lesion became itchy over time; like a mosquito bite. If I had let it bite me longer no doubt a somewhat worse lesion would have been the result; but I have a fairly low tolerance for pain.

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