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Yep, people buy widow spiders. Particularly the red widow ( Lactrodectus bishopi ). The spiders commonly referred to as "black widows" are actually three different species of similar-looking widow spiders : the Southern black widow ( Lactrodectus mactans ) the western widow ( L. hesperus ) and the northern widow ( L. variolus ). There is also an introduced species of widow found in the usa, the brown widow, ( L. geometricus ). Black and brown widows sell for between $5 - $15 each, and red widows for as much as $35. Some people don't need to buy them, but collect them in the wild themselves.

Thanks so much for your answer. I've seen brown spiders with the same body shape as the black widows that we have around here (with the red hour glass on their bellies). So what kind are the widows that live in the El Paso, TX ... Las Cruses NM area, or do all the species that you mentioned live in this area? Just curious.

MissHisssss

You would have Lactrodectus hesperus, the western widow, the brown widow ( L. geometricus ) and perhaps the southern widow ( L. mactans ) as well. The brown widow's bite tends to be less severe than the black widows, but is still not to be taken lightly by any means. A sure way to distinguish brown widows from the look-alike and harmless American house spider ( Achaearanea tepidariorum ) is to look at their egg sacs. House spider egg sacs are smooth and papery, whereas brown widow egg sacs are covered in small tufts of silk.

Thanks so much for the explaination. It's very interesting. Never knew there was more than one type of black widow. How can you tell the black widows apart? By their size? The shape of the hour glass?

MissHisssss

You can tell them apart based on coloration, and, since they live in different parts of the country, their location. ( some widows do have overlapping ranges, so areas of the US have more than one species. ) The northern widow ( L. variolus ) has red spots on the TOP of the abdomen, as well as white spots on the cephalothorax ( head / chest segment where the legs connect ). The hourglass of the northern widow is usually separated into two elongate markings. The western widow looks much like the southern widow, except that their hourglass sometimes appears as two spots, instead of a perfect hourglass. However, the only place western and southern widows are found together is Texas, so they can be told apart based on where they are found. Northern widows can be found as far south as northern Florida, but their appearance distinguishes them from the southern widows.

Tufts like this but you may have already seen this in the spider forum.

Regards,
JDN

WOW what wonderful responses and explainations. THANKS!! Is that spider in the photo with the tuffed egg sacs a brown one? The spiders I've seen that are shaped just like a widow are very very light brown...like tannish. And I don't think they have hour glasses, but don't quote me on that.

And speaking of egg sacs....it seems that every one I've ever seen squashed, is empty (no liquid, etc)... so where are the babies? Then too... do people ever put these sacs in a jar to try and hatch them out, and if so... how long would it take for them to hatch?

Sorry for all the qustions. Just stuff I've been wanting to ask and now I get a chance to do it. Thanks again

MissHisssss

I'll leave most of your Q's to the experts as I certainly am not one. Just somebody who came back from vacation and found Brown Widows had set up housekeeping a little too close for my comfort. This resulted in my quick education in Widows in general and what I could expect to find here in my area of Fl. Quite a few as it turns out including the Red which I hope to get some pics of the next time I'm herping the Palmetto scrubs around here.
Yes that is a Brown Widow in the Pic.

Regards,
JDN

Are you sure? That spider in your pic looks more like an immature L. mactans to me. Or, maybe it is just an abnormally dark brown widow. Here is a pic of a confirmed brown widow :

www.petbugs.com/caresheets/L-geometricus.html

and

http://www.arachnology.org/Arachnology/Pages/Pictures/lgeom3.jpg

Thre darkest brown widow I've ever seen was this :

http://www.arachnology.org/Arachnology/Pages/Pictures/geometri.jpg

But in either case, those are what geometricus eggsacs look like, so while it could be just a very, very dark geometricus, the other two pics in gave are what they more typically look like.

Venom,

Dunno, that's why I said I was not an expert. I was going on the egg cases alone which I understood through my admittedly limited research, was a defining factor. I at first thought I had southern blacks and browns but then changed my mind.... I defer to your expertise. Whadya think? Frankly I was focused on the hourglass, which seems to be less distinct in the brown than the black....I'm confuzzed. I can still retrieve samples if you want some post mortem shots.

Why would a different species occupy a web containing BW egg sacs?

Regards,
Jeff Nichols

Chances of a mactans x geometricus? Do we have something special here?

Regards,
J.

Would one widow eat another widow? I know they often eat the males?

The links were helpful. I see the lighter shade of brown I was talking about. Thanks.

MissHisssss

Greetings.
I am no expert by all means, however I have been keeping widows for many years. They seem to have a simple train of thought: If it jingles the web it's potentialy dinner. If it does not, they seem to ingnore it. I have fed them many types of insect & arachnid in the area. Web building spiders often get ignored for quite some time until they attempt to eat something you drop in there and winds up becoming dinner as well. When spiders drop into the web(other widows included) they get treated like any other potential prey items.

The widow there is brown and has slight banding on the legs, so I think it's a brown, also. Although I probably know the least about spiders here as I despise many of them--but not widows. Anyway, I think the eggsac tells it, but I've seen brown widows in South Florida where I live almost that dark, too.

Hybrids are sterile 99% of the time, so since the spider has egg sacs, we can rule that out. I think that in fact it is a brown widow, from the leg banding, and because the bottom of the hourglass is pointed, instead of flatbottomed as in the southern widow. Its strangely dark coloration may be an instance of variation within a species, as in the peppered moth, which can be black with white flecks, or white with black flecks, and yet both versions are the same exact species. So either it is a hereditary color morph, or L. geometricus has great potential for color variations within the species. Someone should breed one of these, to see whether both colorations can come from the same egg sac, or if light-colored brown widows have light-colored offspring, and dark specimens have dark offspring. There is another instance of this happening in the arachid world, in which there are two distinct color morphs of the same exact species, and each morph has offspring that retain the coloration of the parents. That spider is the tarantula Pterinochilus murinus. It comes in two morphs, the well known "Usambara orange", and the "sunburst baboon" morph. Although it is the same species as the sunburst baboon, you can breed two Usambaras together, and their offspring will all have the same bright orange coloration typical of the Usambaras, and not any of the sunbursts' yellow green coloration. So while they are the same species, the coloration of each is hereditary. This is what I think may be the case with the brown widow.