Just in Case You Weren't Paranoid Enough - Essay about Brown Widows and their Range

[OldSchoolYoungin]

TL;DR version: Brown Widows are becoming just as common if not more common than the infamous Black Widow in many parts of the Southern and Western US. Their venom toxicity is somewhat unknown, but most agree that they're still a medically significant spider.

Decided to write this up after making an interesting discovery in my garage today. Black Widows are as common as houseflies where I am, but the only place I've ever seen a Brown Widow was in Georgia. Behind a lawn chair that's been sitting there for quite some time was the tell-tale, distinctive egg sac of a Brown Widow. Chances are that many in the Southern and Western states have come across these curiosities in the past:

Note: NOT my picture.



No, a civilization of tiny, war-loving humanoids aren't planting land mines under the handle of your garbage can; you have Brown Widows in your vicinity.


What in the hell is a Brown Widow?


Well, that's a good question considering most don't even know they exist. The Brown Widow's scientific name is Latrodectus geometricus, which includes it in the same genus as Black Widows and Red Widows. Actually, there are several species of Widows living in the US: the Southern Black Widow, L. mactans; Northern Black Widow, L. variolus; Western Black Widow, L. hesperus; Brown Widow, L. geometricus; and the Red Widow, L. bishopi. The first three Black Widows are very common and their common names somewhat indicate their range. However, in many cases, the ranges overlap and you may find two different species in the same area. Respectively, the Southern BW is most common in the Southern and Eastern US; the Northern Widow is more commonly found northward but it's range also overlaps with the Southern; and the Western Widow is more or less relegated to parts of the Mid-west, Western and Southwestern states.

The Brown, on the other hand, is very much new to the USA. It's origin is still somewhat mysterious, but most experts believe they may have originated in either South Africa or South America. Nonetheless, they didn't make much of their appearance known until about ten to twelve years ago when they began being seen in Southern California and Florida. Since then, their range seems to grow more and more by the day. Just a few years ago, they weren't known to live in Georgia, South Carolina and even in Tennessee; yet, here they are. Anecdotal reports claim they're also now in Mississippi, Louisiana, and Alabama but those are currently undocumented. It's entirely possible they've been here much longer and were simply mistaken for Common House Spiders, but I'll get to that later.

Habits, Habitat and Appearance

The habits and habitat of the Brown Widow closely resemble that of Black Widows. They're commonly found under debris in dark areas like under rocks, piles of wood or bricks, etc.; unfortunately, they're also very common around areas of human habitation. In fact, Brown Widows seem to love the "company" of humans much more than their Black relatives. Some of the most frequent encounters are made around porches, patios, under outdoor furniture, under children's toys left sitting outside, and in and around outdoor trashcans. They seem to especially love making their webs under lawnchairs and under the handles of the aforementioned garbage cans or anything else where you put your hand

As far as habits are concerned, they're very shy creatures; much more shy than Black Widows, actually. They're not prone to bite even when protecting their eggs, much unlike Black Widows who will zealously defend their offspring. Nonetheless, the species WILL bite if mucked about with too much or if they happen to be trapped between something else and your skin (under your clothing, etc).

Appearance is where things get so iffy. To the untrained eye, the Brown Widow bears a striking resemblance to the Common House Spider, Parasteotoda sp. of which practically everyone has seen and there are probably several in your house as I type this. The Parasteotoda are incredibly common and of no medical significance, yet are closely related to Latrodectus and exhibit many of the same attributes.

Appearance of L. geometricus is as follows:

- Medium sized, normally topping out at no more than 1 to 1.5" legspan. Sometimes the actual size can fool you, though, because if a female has just fed or is full of eggs her abdomen might be be bigger than a dime.

- Tan to brown mottling on the abdomen, possibly with darker or red or white accents. Underneath the abdomen, though, is the tell-tale hourglass. The color of the hourglass can range from yellow to brownish-orange. This characteristic separates it completely from the Common House Spider.

- Tan-ish legs with dark brown stripes at each leg joint.

- The web is normally "hackled" but distinctive. It's often very strong for a spider it's size. At times, there's also a very strong "half cocoon" at some point at the upper region of the web where the spider goes to escape predators or any other disturbance. Their egg sacs are very distinctive, also, which you can see above.

Again, this species is very easily confused with the Common House Spider, so here's a little pictorial to point out the difference. All credit goes to the photographers as none of them are mine.

Edit: Instead of taking up so much space, here's an excellent summation of their appearance in pictures - http://sarasota.ifas.ufl.edu/ipm/brownwidow.htm

Also, here are pictures of the common and harmless Parasteotoda that it's often confused with. Lots of color variation, so just browse around: https://www.google.com/search?hl=en&...AaHk6QHk-o3fCg

Toxicity to Humans

Here's the fun part! Exactly how venomous are these critters? Unfortunately, there's still a lot of controversy over it. Some arachnologists submit that they're even more toxic drop-for-drop than the infamous Black Widow. However, they're not capable of injecting the large amounts of venom that a Black Widow can, so their "danger factor" isn't well documented. An entomologist at the San Diego Natural History Museum says that their venom is, "twice as potent as a Black Widow, but they only seem to inject half as much". So, doesn't that make it just as venomous as a Black Widow?

Other experts contend that Brown Widows and Black Widows have the same venom toxicity, but still agree that the Brown Widow doesn't inject as much. Still yet, being bitten by this species would be no fun at all. Considering it likes to dwell very close to humans, I think they should certainly be a concern. Currently, there's still a lot left of information left up to scrutiny.

So there you have it. Folks in the Southern and Western US may want to pay closer attention to those "house spiders" and cobwebs they have in the corner of their houses and garages. Again, I didn't really expect to see signs of Brown Widows here in South Carolina, but they're evidently here. I'll be hunting for them if I get the chance and it will certainly post up pics of whatever I find!

[Oblique Human]

Interesting read. Thanks.

[oakeshott]

Well, that's a bummer of a thing to find out on Memorial Day.

While I'm the official snake remover of the family and have removed snakes from our basement, steps, driveway, living room (it literally fell from the ceiling during a Giants/Redskins game-6 feet long and hit the back of my lazyboy before landing on the floor behind me...waited till the two minute warning before getting up and looking to see what it was), spiders give me the willies. To paraphrase Orwell, "no legs good, eight legs bad". I no longer kill them indiscriminately and came years ago to a live and let live agreement with them, but they still creep me out.

And now there's a whole new venomous member parading around as one of the good guys. This is terrible news. Any chance they eat the equally new to our shores Brown Marmorated Stink Bug? That would at least be something.

Geez, never gonna get to sleep now.

[Legion]

LOL. Australia.

[Kairtane]

LOL. Australia.

You owe me one monitor cleaning.

[OldSchoolYoungin]

LOL. Australia.

I genuinely feel sorry for you guys, sometimes.

[cb91710]

As a traffic signal technician, I am finding more Brown than Black, but the locations do vary.
I'm still finding black inside of the cabinets and buried down in the wire pull boxes, where the browns are much more common on the exterior of the cabinets around the doors, and I even found one that had spun her web from a pole at about ankle height down to the sidewalk... egg sacs and all.

But the black widow is fighting a losing battle in the San Fernando Valley. I'm seeing far, far fewer black widows in the last couple of years... yet I'm not yet seeing brown widow evidence out where I live in the inland empire.

[oakeshott]

I'm officially paranoid. We were working out in the yard today and I decided to leave a small wood/brushpile just where it was and it was all because of this post. The Pax Aranea may have ended today.

[The Count of Merkur Cristo]

Exellcent read, but the Mrs. and I are 'scared shitless & freak-us-out' about all manner of spiders.

"Will you walk into my parlor"? said the spider to the fly. "Tis the prettiest little parlor that ever you did spy". Mary Howitt

[roklein]

Thanks for the info. I have no tolerance for any spider and death comes quickly to those that cross my path. If you like them, that is your business.

[OldSchoolYoungin]

But the black widow is fighting a losing battle in the San Fernando Valley. I'm seeing far, far fewer black widows in the last couple of years... yet I'm not yet seeing brown widow evidence out where I live in the inland empire.

I have a friend in Southern Georgia that works in pest control and has said the very same thing; lots more brown, lots less black in recent years. The Black Widows are still pretty common around here but I've also seen a decline, lately. Also, I've seen a very stark decline in Northern Widows, especially. Almost makes me feel special to have been bitten by the largest female I've ever seen...or not

Just curious - I'm assuming that most Black Widows out your way are Western Widows, which are the biggest in the Widow family. I've heard reports of deserted (literally) specimens reaching 3"+ legspan. What are the biggest you've seen?

Sorry, I'm a spider geek and these kinds of things interest me

[cb91710]

Largest I've seen has probably had an abdomen a bit larger than a (shelled) peanut, legspan maybe a bit over 2"

I have seen some pretty big orb weavers.

[OldSchoolYoungin]

I'm officially paranoid. We were working out in the yard today and I decided to leave a small wood/brushpile just where it was and it was all because of this post. The Pax Aranea may have ended today.

No worries, dude. Or, maybe, not MANY Brown Widows are now stretching across the Southeast in large numbers, but I'm not really sure about VA. There have been claims of them being found there, but it's not yet a part of their official range. Then again, just a few years ago, their continental US range consisted only of Texas and Florida; it's certainly possible they've made their way up to VA by now.

If it makes you feel any better, Brown Widows are extremely shy and not prone to bite, even moreso than their Black Widow cousins. Then again, "enthusiasts" and "scientists" claim that Black Widows aren't very defensive, either. I beg to differ after seeing tons of them in action. Northern Widows, in my experience, are also more defensive than their Southern Widow brethren. I kept one that would viciously defend against any and all disturbances around her. She "karate kicked" (tried to entrap with sticky webbing) anything that entered her territory, which meant she was about to turn around and bite the crap out of it.

Hope this post is useful and makes you sleep better tonight

[OldSchoolYoungin]

So never found one of the little buggers despite looking all over the place. Low and behold, today at work, there's a spider crawling on my leg. Sub-adult female Brown Widow of all things! She must've been out of her web for a while; she's very emaciated and could barely crawl. She's currently in rehab and I think it's working

Most certainly NOT an immature or male Black Widow as they're commonly mistaken for. The brown mottling on the dorsal surface isn't very clear due to her shrunken abdomen, but the bottom reveals the yellow-outlined hourglass characteristic of this species.

[martym]

would that also be known as a brown recluse or is that some entirely different spider?
marty

[oakeshott]

So never found one of the little buggers despite looking all over the place. Low and behold, today at work, there's a spider crawling on my leg. Sub-adult female Brown Widow of all things! She must've been out of her web for a while; she's very emaciated and could barely crawl. She's currently in rehab and I think it's working

Most certainly NOT an immature or male Black Widow as they're commonly mistaken for. The brown mottling on the dorsal surface isn't very clear due to her shrunken abdomen, but the bottom reveals the yellow-outlined hourglass characteristic of this species.

oh man. why'd you have to include pictures?

[OldSchoolYoungin]

would that also be known as a brown recluse or is that some entirely different spider?
marty

It's a Brown Widow Spider, completely different than a Brown Recluse.

[bamafan64]

I can find dozens of black and brown widows at the refinery I work at. There are probably four browns to every black widow, so they may be displacing the black widows. An interesting little tidbit on the black widows-we have lots of fiddler crabs running around in the production units due to us being so close to the Gulf and I have often seen dead fiddler crabs in the black widow webs. I wouldn't think they could penetrate the crabs shell but they do.

[BingeAndPurge]

Read this last night. Walked onto my deck an hour ago, and wouldn't you know it, a brown widow egg sack hanging above my back door. Half full: glad I read the thread and could recognize the sack and know to be a little more careful. Half empty: I am now even more paranoid about the area I just moved to (NC), and would almost rather be ignorant of it.

I moved here from Ohio a few weeks ago. The wildlife and insects are a completely different ballgame here.

[nymtber]

AH, living in NY has its benefits. Been a report or two of brown recluse bites, but doesnt seem as populated up here.

Sure hope it stays that way! We do have ticks, though. and skeeters.

I kill any spider in our house that is NOT a daddy long-legs. Those dont bother me, everything else goes.