Scary specimens!

I don't know about you, but I still get a big kick out of Halloween. I like all of the pumpkins and candy and decorations, and the crisp feeling in the air - especially today after that cold front! Anyway, over the years I've noticed that one little invertebrate seems to be featured around this time of year in various decorations - the black widow spider.

Most people are very familiar with the black widow spider (genus Lactrodectus). They're easy to spot, and it's hard to mistake them for something else - most of the time. More than likely, if you live in the United States, you're quite familiar with this gal here: 

http://en.wikipedia.org/wiki/File:Black_Widow_11-06.jpg

Beautiful, isn't she? Black widows are certainly very striking spiders. Here is a great close-up picture of her hourglass marking. It serves as a warning, saying "Danger! Do not mess with me."

http://en.wikipedia.org/wiki/File:Blackwidow_macro.jpg

Female black widows are the ones that are particularly dangerous to humans, as her bite contains much more neurotoxin than that of a male black widow. Black widow bites can cause severe pain and cramps in humans. In rare cases it can be fatal, but more than likely the bite just leads to a very unpleasant experience.  

Male black widows look much different than females. They are usually more of a brown color, but also have some white and orange coloration as well. They're smaller than females, and sometimes have the unfortunate fate of being snacked on by the female after mating. They are not dangerous to humans. Below is a picture of a brown widow - unfortunately I could not find a usable male black widow photo. I think that they look similar in to this brown widow, both in coloration and body structure, except for the hourglass - males don't seem to have those.

http://en.wikipedia.org/wiki/File:Brown_widow_spider_Latrodectus_geometricus_underside.jpg

Black widows tend to have very tough and sticky webs, and they look chaotic and somewhat half-hazard. When we think of spider webs, we usually think of round, intricate webs that have a pattern. Not so with black widow webs. If you see a web like this outside, stay away. Black widows will leave you alone if you leave them alone. 

We do have some black widows in our collection. Something that I've noticed is that when they are kept in ethanol, their red hourglass turns white or sometimes even a chartreuse color. 

This spider is in a large jar of spiders in the black widow family, Theridiidae. You can just barely see the hourglass that has turned white from the ethanol preservation. The spider is upside down, with the abdomen facing up towards the top left of the vial. 

Happy Halloween, everyone!