I caught a spider in my bathroom and it looks like a recluse type. However, the internet spider authorities claim there are no Brown Recluse spiders in the San Francisco Bay Area. Those are the truly dangerous spiders and they are mostly within a couple hundred miles of the lower Mississippi River. Even there they are uncommon. There are other types of recluse spiders however and they may have a similar type of venom just not so much of it or at least not quite so nasty.
The Brown Recluse Spider has a violin shape on its back between the shoulders which my spider apparently does not.
However, to be sure I took another photo and did a PhotoShop enhancement of the whole picture to make the color and contrast more vivid. That makes the spiders thorax more visible. For more comparisons look at the online photos linked to below but proceed with caution because there are some are really ugly ones, much worse than mine which is bad enough – really ugly spider bite photos –
This photo was taken about four days after the what my dermatologist thought was a spider bite. I didn’t get an appointment see her for another week after this picture was taken. However, at the time I did see her I didn’t have the spider only the somewhat improving wound. It was a bit better than the photo above but not much. This morning I caught the spider seen in the photo at the top in my bathroom and managed to get it a new home in a small clear plastic box. It may not be the right spider but I haven’t seen a spider in my house for over a year so it’s likely to be the right one.
[My present camera is a year old 15 megapixel Samsung TL34Hd. It doesn’t take pictures closer than about 16 inches which means I had to crop down quite a bit to the relevant part of the image. I have an older camera, a Casio Exilim EX-Z1000. It’s a 10 megapixel one which has been on the shelf for two years but which I think will take a much closer picture so there should be a better picture soon. But first the batteries have to be recharged. [My second photo above was taken the next day with the Casio.]] See also:
[Update 2010-09-13] This spider has been professionally identified as Steatoda grossa which has a medically significant spider bite. If this spider caused the nasty wound seen above it becomes imparitive to really avoid the really nasty ones.