October 31, 2014
Photos by Kathy Kinsey and Danie Turner
By Kathy Kinsey
‘She was a long cool woman in a black dress’ always comes to mind when I think about the Black Widow. And though she may not be too cool to some of you, she is probably the most recognized black spider. With long, slender legs, she is dressed in black patent with a touch of red. Who doesn’t like those two colors together? But not all widows sport the color red because some may show no markings at all. But there are characteristics that will help you identify such a spider for the Black Widow is as wicked as she is pretty. But like most wicked insects, she also has her place in the world.
The Black Widow Spider belongs to the family Theridiidae, genus Latrodectus. All young spiderlings are considered cannibalistic while in the egg sac. The life cycle of the widow is normally one year but some have been known to live up to 3 years. They are all armed with neurotoxic venom. All the females bite. Smash. Ask questions later.
The Northern Black Widow (Latrodectus variolus) is considered an east coast spider. Found in North Florida to southeastern Canada. She is just under ½ inch (excluding legs). The hour glass on her abdomen is distinct, but broken and typically there is a row of red spots down the middle of her back – as you can see in the photo. Though slightly smaller than the others, she is considered “not quite as venomous” – but still not to be messed with. Egg sac is brown and paper-like.
The Southern Black Widow (Latrodectus mactans) is considered to be the original Black Widow and has been found as far north as New York, south to Florida, west to Texas, Oklahoma and Kansas. She has also been found in California which indicates she may be found in all the southern states. She is about ½ inch in length (without legs). Juveniles start out brown, white and orange turning black as they mature. The hour glass on the abdomen is complete and can easily be seen as most widows hang upside down in their webs. She also has a red spot just behind and above the spinnerets. Egg sacs are white at first then turning to tan or gray in color.
The Western Black Widow (Latrodectus hesperus) is found in the extreme southwestern area of Canada, south into Mexico along the Pacific coast and east to Texas, Oklahoma and Kansas. She is also found in all four deserts of the American southwest. Measures about ½ inch in length, (excluding legs) with a complete hourglass shaped red mark on the abdomen, but this mark may also be yellow or in rare occurrences it may be white. Females develop into a shiny black or dark brown color with a bright red or orange hourglass as they grow older.
The Red Widow (Latrodectus bishopi) is uncommon and found in the southern and central areas of Florida, primarily in the sand pine habitats in Marion to Martin County. Webs are low to the ground and are built in and around palmettos, rosemary, scrub oaks and other shrubs known to this area. This widow has a reddish orange head, thorax and legs with a black abdomen. On the top of the abdomen, there is a row of red spots with yellow borders. No hourglass on this widow but usually has one or two small marks instead. Egg sac is white and smooth. Actually, this one is kind of ugly!
Widows also come in brown, though a little harder to find. The Brown Widow (Latrodectus geometricus) has the same neurotoxic venom, but their bite pales in comparison to the Black Widow because she can’t deliver the same amount of venom so their bite is not as bad, as statistics go. This is a widow that is highly variable in the color range – from almost white to almost black with an orange to yellow hourglass marking on the abdomen. Egg sac is tan in color and resembles a sandspur which may be the best way to identify this one as she is the only widow with this type of egg sac. She is the most actively reproducing one as well with 5,000 young per female per season. Ranges from Florida to Georgia and South Carolina and has been seen in California, Alabama, Mississippi and Texas.
With unusually large venom glands, she is considered a particularly dangerous spider with a bite that is felt almost immediately, increasing in pain for 1 to 3 hours. The pain from this bite may last up to 24 hours or longer. The venom is a neurotoxic which means it blocks the transmission of nervous impulses and is thought to be 15 times stronger than that of a rattlesnake, causing abdominal pains, fainting, dizziness and chest pains. High blood pressure and a higher heart rate have also been observed in bite victims. As with any venomous bite, it is important that you remain calm. Any frantic movement on your part will only move the venom through your system at a quicker rate. Should you suffer a bite from a widow, call 911 for assistance and inform them of your bite. Lack of medical attention may lead to death by suffocation. Thankfully, Black Widow anti-venom was introduced years ago to aid in the recovery of this bite.
Widows are normally found near water and low to the ground. They like dark, undisturbed areas but I have found this is not always the case with this spider. I have found them in the trunk of a car and right inside my carport. I have also found them in and around trees, in stones that make up a flower bed, at the base of spinach, potato and peanut plants, overturned pots…well you get the idea. But ideally, they like dark areas that are undisturbed. Shoes also make an easy spot for them to hide out and your toes make the perfect target, so check your shoes, especially if you go outside at night.
Black Widows make an unorganized mess of a web with their silk. No rhyme or reason to it but it seems to works for her. This very messy web is how I have found so many because no other spider spins this type of web. Though she is not on her web during the day, she is at night. If she is close to the house, her night is over. You see, I have outside cats and if a cat is bitten by a widow, they can die from convulsions and paralysis. So to prevent this from happening, I do them in if they are near the house or where my cats hang out. If I can prevent me or any member of my family from being bit, I will and I feel you would do the same.
So what kills them? Your shoe or a stick I have found works the best. Soapy water does not do it, however, it will cripple her just enough so that you can do your thing. You need to make sure there is no egg site near the web – you will want to destroy it as well or else all your efforts will be for naught. You might want to check the UF/IFAS website for a pesticide that will work on them but be careful using pesticides. I am not a fan of them and as you will only find one spider on the web, once you hit her with some soapy water, she will be available for a good stomping. Just make sure you bury her so no one steps on her fangs. The stick will help you accomplish this. The good thing about the Black Widow, she is not an aggressive spider so she is not going to mess with you if you will leave her alone.
The venom of the widow (female) is three times more potent than that of the male, a smaller spider that usually meets his death after mating, but not always. Some manage to escape to live and mate another day. I have never seen one of the males but I have seen plenty of the females. Their first reaction is to curl up when disturbed – unfortunately for her, this is not my first reaction. You have to feel for her though. The way she has to eat…digesting a liquid bug is what it amounts to, putting it mildly for the more sensitive readers. But then all spiders do this. Even the common house spider does this, of which I allow a few safe refuse in my house – yes, in my house. You see, they like nasty roaches. Anything that will eat a roach is my friend and should be yours, too. It is a great thing actually. They eat all the bugs that either bite or chew on plants. And I hate bugs in my house even more. Black Widows are nocturnal as are house spiders so you never see them while they clean up the bugs.
Though rare, small children, the elderly and the feeble or weak in body and health have died from just such a bite. I thank my lucky stars that I have not experienced this bite and I do not ever plan to. I have heard about the bite and it is nothing I care to experience. And though I have no serious fear of spiders, I have as much respect for this spider as I do any insect that has a healthy supply of venom. Thankfully, she is preyed upon by the mud dauber, which is a wasp, though in tearing down several of these mud nests, I have yet to find a widow in one of them but I have found several caterpillars and other small spiders in them.
And though I have seen plenty of Black Widows out here in the country, not all of them have met their demise. If she is living in an area that is not frequented by humans or my cats, I will leave her alone simply because she poses no immediate threat. Flies, mosquitoes, grasshoppers, beetles and caterpillars are on the menu. But roaches are abundant in the country and I have seen several roach carcasses near their webs. And of all the bugs in this world, I simply hate roaches – all sizes!
So what happened to the widow in the picture for this article? I returned her to the mess of a web she calls home. She and her black, plastic flower pot will be moved to an out of the way place where she poses no threat to anyone and will be able to do what she does best. Besides, she was just too gracious to sit for all the photos that were taken to end her life! And for all the bad that is written about her, she is a bugger. So to that I say…….
Live on you long cool woman in a black dress!
Kathy Kinsey is a Master Gardener volunteer with the UF/Leon County Cooperative Extension Office. For more information about Black Widows or spiders in general, or maybe gardening in our area, you can visit our website at http://leon.ifas.ufl.edu . You may also email us at Ask-A-Mastergardener@leoncountyfl.gov with any gardening questions you may have.