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Identifying a spider very similar to a brown recluse

Identifying a spider very similar to a brown recluse


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I took this pic tonight when I saw what I thought to be a Loxosceles reclusa or brown recluse. But when I looked closer, the typical pattern on the back of its cephalothorax seems to be upside down! I tried to compare with lots of pics and I was not able to identify this one. Plus, its abdomen is kind of velvet greenish. Could anyone help identifying this spider please? Last precision : the body size (excluding the legs) is around 1cm. Thanks Folks! Photo taken on June the 24th 2018 around 10pm in Toronto, South Ontario, Canada. PS: Even if one of its leg is fully missing, it was still running very quickly…


I think this a nice male Cheiracanthium inclusum, the familiar "yellow sac spider" (outdoors edition). The abdomen is what you would expect, the very long first pair of legs, the obvious eyes at the front of the head (middle two of the top row). I'd feel more comfortable if I could see the usual very dark 'face' and chelicerae, but the angle of the photo is such that it might be just hidden. The carapace pattern looks interesting, but it may well be that the flash of the photo is giving us a different look there.

Here's the link to the Bug Guide page, with a representative photo of a similar male:

https://bugguide.net/node/view/80427


Identifying a spider very similar to a brown recluse - Biology

Posted on 12/04/2020 6:03:37 AM PST by Red Badger

A tiny brown invasive species of spider that's creeping its way across the UK has a dangerous reputation for dissolving flesh, one that many experts have argued isn't deserved.

There's now compelling evidence suggesting that stories of the false widow spider (Steatoda nobilis) causing horrid skin infections has at least some basis in fact.

The false widow has called the UK home ever since it was spotted on its shores in the 1870s, most likely having hitched a ride from Madeira and the Canary Islands off the African coast.

In recent decades its range has widened to reach as far as Ireland. Given it loves a warm home as much as we do, encounters with the eight-legged migrant have only increased as more people have been forced to stay indoors in 2020.

Unfortunately, not all meetings are friendly ones.

"About 10 species of spiders common in north-western Europe have fangs strong enough to pierce human skin and deliver venom, but only one of them, the recent invasive noble false widow spider, is considered of medical importance," says John Dunbar, a zoologist at the National University of Ireland (NUI) Galway.

In most cases, the worst you might expect from a false widow spider bite is a few hours of pain around the injection site, and maybe a day or two of stiff joints. No worse than a wasp sting, really.

It's not the venom we need to be concerned about though – it's the risk posed by bacteria found on its fangs.

Every now and then a story will hit UK headlines of an arachnid bite leaving victims with something far worse than a throbbing finger. Swollen hands, rotting holes of pus, threats of amputation, or even deaths have provided ample nightmare fuel.

Though formal identification isn't always possible, the false widow typically cops the blame regardless.

Experts have understandably come to the spider's defence, arguing that even if it is guilty of leaving a couple of holes, it's the victim who supplies the necrotising bacteria by scratching at the site with dirty fingernails.

Hard evidence in support of either explanation has been scarce. So Dunbar's team collected specimens of false widows along with some lace-webbed (Amaurobius similis) and giant house spiders (Eratigena atrica) from gardens and pathways, and took them back to the lab.

There the arachnids had their bodies and chelicerae (appendages by their mouth parts) swabbed for bacteria, and venom collected from the false widows.

The venom was used to test suggestions that the venom might help keep their fangs sterile enough to prevent them from inoculating victims with a dose of germs as they bite.

RNA analysis did reveal a rich variety of microbes present on the spiders. Nearly a dozen genera were identified in total out of 22 bacterial species found on false widows, 12 were potentially pathogenic to humans.

"Our study demonstrates that spiders are not just venomous but are also carriers of dangerous bacteria capable of producing severe infections," says NUI Galway microbiologist, Neyaz Khan.

We're not exactly talking plague-spreading monsters here, with most of the microbes of a variety you'd find just about anywhere (many including our own bodies).

There were, however, a handful that demonstrated worrying grades of resistance to antibiotics - that is where the real concerns arise.

"The biggest threat is that some of these bacteria are multi-drug resistant, making them particularly difficult to treat with regular medicine," says Khan.

Thanks in part to our overreliance on antibiotics in both medicine and in maintaining the health of livestock, drug resistant 'superbugs' are a rapidly emerging threat we need to take seriously.

The good news is all of the microbes could be treated with a course of ciprofloxacin, a common antibiotic. For now, at least.

Knowing a spider's bite can transfer superbugs shouldn't make us fear spiders – it's a risk we increasingly face from many facets of life, after all. Besides, the chances of a bite for the vast majority of people are small, let alone of developing a deadly infection.

But understanding the potential for a drug-resistant infection from even a couple of tiny punctures could help save lives.

"This is something that health care professionals should consider from now on," says Khan.

This research was published in Scientific Reports.

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Southern House Spider

The southern house spider is most common throughout Florida, but it can also be found frequently in the other states of the southeastern U.S. Because of their color and general shapes, males are often mistaken for brown recluse spiders. These spiders are not known to be dangerous, but their bite can cause pain for a few days. Their webs can be found in the corners of overhangs, windowsills, and shutters.


Brown Recluse Spider Facts & Information

What Does a Brown Recluse Spider Look Like?
Marking: The most telltale characteristic of brown recluse spiders is the presence of a dark, violin-shaped mark on the dorsum of the arachnid's light brown or yellowish-brown cephalothorax. The neck of this distinct violin pattern is directed toward the abdomen. Due to this marking, brown recluses are also commonly known as fiddle-back spiders. Baby brown recluse spiders do not have this distinctive marking. It develops as the spiders grow into adulthood. To positively identify a spider as a recluse, both the eyes and fiddle marking must be seen, since other spiders may possess one or the other characteristic alone.


Brown Recluse Spider

How Did I Get Brown Recluse Spiders?

Like many spiders, the brown recluse spider likes to stay secluded in dark corners of places that are rarely disturbed or cleaned. Inside locaations such as voids between and under kitchen cabinets, storage areas and basements inside houses can provide plenty of areas for these pests to hide. Outside these spiders may inhabit sheds, barns and garages and may unknowingly be brought inside a home when moving stored items inside. The abundance of prey insects can lure a brown recluse spider inside the house, as well as provide a sustainable source of food should they get inside a home.

How Serious Are Brown Recluse Spiders?

The pests lay up to five egg sacs with as many as fifty eggs in each. This can quickly escalate an infestation. While they typically refrain from attacking humans, brown recluse spiders will bite if provoked. This often occurs when people step on the pests or roll on them while sleeping. Bites can result in lesions, nausea, and fever.

How Do You Get Rid of Them?

The Orkin Man™ is trained to help manage brown recluse spiders. Since every building or home is unique, your Orkin technician will design a special program for your situation.

Keeping spiders out of homes and buildings is an ongoing process, not a one-time treatment. Orkin’s exclusive A.I.M. solution is a continuing cycle of three critical steps — Assess, Implement and Monitor.

The Orkin Man™ can provide the right solution to keep spiders in their place. out of your home, or business.

Signs of a Brown Recluse Spider Infestation

The most likely sign of recluses are sightings of the spider.

Behavior, Diet & Habits

Brown recluse spiders dwell in many of the same dark, sheltered places as black widows. They can be found in homes, barns and basements. Webs tend to appear disorganized and are built most commonly near ground level. The spider is a hunter, so the web is not intended to catch prey but instead roams around searching for prey. The brown recluse is found in the central southern part of the U.S., from Texas to the western most part of Florida.

Brown recluse spiders are shy and rarely bite unless provoked. Bites usually go unnoticed until effects manifest a few hours later. Most bites become red and fade away, but in uncommon cases necrosis or tissue damage can occur. A medical professional should be consulted if there are medical concerns.

More Information

Although urban myth purports that they are found throughout the U.S., studies have shown otherwise. Brown recluse spiders are endemic only to the American South and Midwest. Relocation of the brown recluse can occur in boxes or items moved from its native range. These usually are isolated events and do not result in an entire area becoming infested.

Many conditions are mistakenly diagnosed as brown recluse spider bites, including Lyme disease, diabetic ulcers, reactions to medication and bacterial infections.

Due to misinformation and fright, many people identify harmless spiders as brown recluses. They are also referred to as fiddleback spiders due to a distinctive marking on the thorax, which resembles a violin. Brown recluses have uniformly colored legs and abdomens so any spider exhibiting distinct color variations and patterning on the legs or abdomen is not a brown recluse.


How to Identify False Black Widow Spiders

Spider younglings are often hard to distinguish from other spider species. Most adult female widow spiders have a glossy-jet black coloration, a red or orange hourglass, or similar such marking on the underside. They are about the size of a ½ dollar coin spin a &ldquosticky,&rdquo irregularly shaped web.

Male Widow Spiders

To further complicate matters, male widow adults are smaller than typical female adults. Males can have reddish and whitish makings on the top, not the underside of their abdomen, with shapes that include stripes or spots as well as an hourglass.

Black Widow Species

Insect experts classify true widows in the genus Latrodectus. True black widow spiders found throughout the United States include the southern black widow (Latrodectus mactans) the northern black widow (Latrodectus variolus) and the western black widow (Latrodectus Hesperus).

Spiders That Look Like Black Widows but Aren't

Immature brown widows and western black widows look very much alike when they are young. Adult brown widow females have a reddish hourglass marking on the bottom of the abdomen, but are often more of a tan or dark brown color rather than black.

However, this color distinction is not always easy to see. A black widow with an hourglass marking will display the shape prominently, whereas brown widows will have a less distinctive, duller marking. Also, brown widow bites are less painful than the bite of the western black widow.

Red widow (Latrodectus bishop)

Adult female red widow spiders are reddish-orange, with reddish colored legs and a black or dark colored abdomen. The top of the abdomen usually has rows of red or orange spots outlined in white or yellow. Females lack a complete hourglass shape on the underside of the abdomen. Instead, they usually have one or two small red marks that look somewhat triangular.

False Black Widows (Steatoda grossa)

This spider does not have the red hourglass marking and is a glossy chocolate brown colored spider. It shares the same rounded-abdomen body form and web-making traits as the true black widow spiders. However, this spider is slightly smaller than a mature western black widow spider. False black widows can bite if picked up or otherwise touched, but its bite is rare and is not considered a medically important spider.

Noble False Widow Spider (Steatoda nobilis)

This spider is somewhat rare in the United States, but is found in California. The adult female has a bulb-shaped abdomen much like the widow spiders. But the abdomen is brown and has cream colored markings similar in shape to a skull. Bites are very rare. Symptoms are minor and discomfort due mostly to the pests large fangs.

Adult domestic house spiders, also known as the barn funnel weaver spider, are reddish-brown and have a pale, freckled abdomen. Their bodies do not have the hourglass marking, vary from gray-brown to dark brown and have two dark colored stripes on the cephalothorax.

The black house spider is a dark colored spider, more bulky and awkward in appearance than widow spiders. Both males and females have dark brown legs and a gray abdomen with light markings on the top of the body. These spiders can bite if disturbed, but are not aggressive. They usually try to escape rather than bite.


Spider Control – Pointe Pest

Despite the fact that spiders are beneficial to keeping many insects and pests at bay, home spider control may be necessary for a number of reasons. First, it will help you avoid webs from appearing in and around your home. Spider control will also help protect your family from spiders whose bites can be dangerous, such as the black widow and brown recluse.

Do you know how to tell harmless spiders from dangerous ones? Which spiders can you carry outside and which should prompt you to call for pest control? Pest control companies have the training to tell the potentially dangerous ones from the ones that are not. Sometimes it’s hard to tell, especially when vastly different species can look extremely similar.

Brown recluse spiders

You have probably heard of the brown recluse spider, a dangerous species whose bite can result in skin lesions in humans. Brown recluse bites are serious and require medical attention immediately. Recluse spiders build irregular webs that frequently include a shelter consisting of disorderly threads. These spiders frequently build their webs in woodpiles and sheds, closets, beds, garages, cellars and other places that are dry and generally undisturbed. These spiders can squeeze through tight spaces and are often near or in a home. Typically about the size of a quarter, brown recluse spiders range from tan to dark brown, with the abdomen and legs uniformly colored. One of the best ways to identify these spiders is by their eye pattern, which is a semi-circular arrangement of six eyes in three groups of two, as opposed to the eight eyes of most other spiders. If you see a brown recluse spider, contact your local professional pest control company.

Black widow spiders

The black widow and western black widow spiders are also poisonous and common in North America. They are characterized by a similar body shape and reclusive habits. Both are shiny black with a red hourglass shape or markings under the abdomen. Black widows are shy, preferring to build their webs in a dry protected location where their prey is likely to travel. Outdoors they can be found among rocks and wood piles, under decks, in hollow stumps, rodent burrows, beneath benches, etc. They prefer basements, crawls spaces, and garages in structures as well as other protected areas. Black widow spiders are not as common in homes as the brown recluse, but when they are found indoors, they are usually found in garages and under appliances or heavy furniture and not out in the open. Black widow spiders are usually timid and will only bite in response to being trapped against skin. With both brown recluses and black widows, bites are very serious and require immediate medical attention.

Our Guarantee

At Pointe Pest Control, your premier pest control company in Pennsylvania, New Jersey, and Delaware.

Our service is backed by the best guarantee in the business. If we do not provide a service to your level of satisfaction, we will promptly return for free until you are satisfied. If the problem persists, we will refund your last service payment.


Spider Control in Cache Valley, UT

Despite the fact that spiders are beneficial to keeping many insects and pests at bay, home spider control may be necessary for a number of reasons. First, it will help you avoid webs from appearing in and around your home. Spider control will also help protect your family from spiders whose bites can be dangerous, such as the black widow and brown recluse.

Do you know how to tell harmless spiders from dangerous ones? Which spiders can you carry outside and which should prompt you to call for pest control? Pest control companies have the training to tell the potentially dangerous ones from the ones that are not. Sometimes it’s hard to tell, especially when vastly different species can look extremely similar.

Brown recluse spiders

You have probably heard of the brown recluse spider, a dangerous species whose bite can result in skin lesions in humans. Brown recluse bites are serious and require medical attention immediately. Recluse spiders build irregular webs that frequently include a shelter consisting of disorderly threads. These spiders frequently build their webs in woodpiles and sheds, closets, beds, garages, cellars and other places that are dry and generally undisturbed. These spiders can squeeze through tight spaces and are often near or in a home. Typically about the size of a quarter, brown recluse spiders range from tan to dark brown, with the abdomen and legs uniformly colored. One of the best ways to identify these spiders is by their eye pattern, which is a semi-circular arrangement of six eyes in three groups of two, as opposed to the eight eyes of most other spiders. If you see a brown recluse spider, contact your local professional pest control company.

Black widow spiders

The black widow and western black widow spiders are also poisonous and common in North America. They are characterized by a similar body shape and reclusive habits. Both are shiny black with a red hourglass shape or markings under the abdomen. Black widows are shy, preferring to build their webs in a dry protected location where their prey is likely to travel. Outdoors they can be found among rocks and wood piles, under decks, in hollow stumps, rodent burrows, beneath benches, etc. They prefer basements, crawls spaces, and garages in structures as well as other protected areas. Black widow spiders are not as common in homes as the brown recluse, but when they are found indoors, they are usually found in garages and under appliances or heavy furniture and not out in the open. Black widow spiders are usually timid and will only bite in response to being trapped against skin. With both brown recluses and black widows, bites are very serious and require immediate medical attention.

Our Guarantee

At Elevate Pest Control, your premier pest control company in Cache Valley, we serve clients in Smithfield, Logan, Providence, Wellsville, Tremonton, Brigham City and the surrounding areas.

Our service is backed by the best guarantee in the business. If we do not provide a service to your level of satisfaction, we will promptly return for free until you are satisfied. If the problem persists, we will refund your last service payment.


Hobo spider vs Giant house spider. Help me learn the difference? Pics and Video of the spider I found.

Found a spider, would like help identifying or confirming my identification. I'm trying to learn as much as I can and would like to know I have my facts straight, and if I do maybe this well help a few people.

I live in WA (about 20 miles north of Seattle). As with most people probably, I have a really hard time distinguishing between Eratigena agrestis (Hobo Spider) and Eratigena atrica (Giant house spider). Both are common in WA it seems. I found this guy in my garage in a lamp fixture while cleaning. So I have a few things I wish that the spider experts might be able to help me out with. I have a few videos of it and some screen-grabs of it. I realize it might be more tough for you to verify since I got to stare at it in person for an hour. Sorry in advance for blurry videos, my phone is off its meds and has a hard time focusing.

I believe it to be a male giant house spider. At least, I was confident enough that it was one to let crawl on my hand. Which may have been dumb if a Hobo, but I like to gently handle the ones I positively identify to a) practice how to and b) they are just cool.

Outdoor Video I know. it's vertical, but it was the easiest way to hold the phone + flashlight

Here are the reasons I believe it to be a giant house spider:

The size - This seems like the biggest give away. The leg length and general size look correct for a Giant house spider and it seems to be bigger than what a Hobo would ever grow to be. However I would like to be able to tell the difference between a small Giant house spider and a normal Hobo.

The palps come to a ball then have a small long point on the end. I believe male Hobo spiders simply have the ball on the end of their palps with no point. EDIT: u/trickycrayon linked pictures in the comments below that Hobo spiders do have pointy palps, just not as pronounced as the GHS.

The sternum - Might be hard to tell in the video, but there are very faint spots I believe, which a Hobo wouldn't have. At the very least it seems to be missing the "bright" stripe in the middle

The colorization was really close, and the guide said it is very inaccurate for truly determining species. However, the bands on the Cephalothorax seem to be distinct in contrast (but still broken up and not a solid line) which made it really tough to tell either way. Google images seemed absolutely terrible for trying to identify it. Searches for each spider seemed to have almost identically patterned/marked results and coloring that was pretty confusing.

More on the colorization. It seems to have a few more distinct black spots towards the abdomen which I thought was uncharacteristic of a Hobo spider. I thought they tend to be more uniform throughout with the "V" pattern like This

The behaviour - It wasn't aggressive at all and when not attempting to run away just kinda chilled and crawled around. This may be a myth from general fear, but are Hobo spiders typically more aggressive?

Also I don't believe hobo spiders are quite as venomous as google-fu says? I think the most reliable source I saw said that their bites were grossly played up as being dangerous (still not fun, but not going to have large patches of skin sloughing off)

The location - I was under the impression that Hobo spiders are really rare to find indoors, but not impossible in garage type enviroments.

Lastly I tried to find a new home for him near some rock structures that seem like a good habitat. There were lots of rock structures and other great hiding spots for a funnel web in that general area. (The girlfriend would not let him continue to live in the house).


Common Spiders in Florida and Georgia

With over 45,000 species of spiders on Earth, many are rare and located in highly specific environments. Most spiders are harmless to humans, however the most notorious spiders are the ones whose bite can cause illness in humans, the black widow and the brown recluse. The other spiders we are naturally more familiar with are the ones that tend to make their way indoors and plant themselves in the highest corner of the living room.

Common House Spider

The Common House Spider, Achaearanea tepidariorum, is the spider that is most likely to be found in and around your home or business. The Common House Spider creates webs to capture prey, and if they web does not yield food, it is abandoned, and another web created. It is this tangled mess of abandoned webs that gets under our skin. The Common House Spider is often found in areas where air currents may bring a buffet of insects. They are common in sheds, garages, barns, and warehouses. Indoors, they can be found in upper corners, closets, basements and crawl spaces, and in the angles of window frames. The Common House Spider constructs webs both on the inside and outside of buildings. Interestingly enough, the Common House Spider is not that common in the wild. It seems to prefer to live in close proximity to humans, on our buildings, bridges, and culverts.

The female Common House Spider is usually between 4-8 mm in length, while the male is usually 4mm in length. The female Common House Spider lives for about 1 year and may produce up nearly 4,000 eggs in her lifetime. The Common House Spider is not considered dangerous to humans only a single incident of a serious allergic reaction to a bite has been documented.

Southern House Spider

The Southern House Spider is the large arachnid that nightmares are made of. If you have a tendency toward arachnophobia, it is likely because this large spider has planted itself in your living room. The Southern House Spider is common in Florida, Georgia, and Alabama and other areas of the South. The Southern House Spider of both sexes grows to be about 2 inches in diameter. The males have longer legs than the females, and are commonly mistaken for the notorious brown recluse because of their similar brown coloring and shape. The female Southern House Spider is charcoal in color and her body is rounder and bulging than the male and she has shorter legs.

Southern House Spiders are sometimes called Southern Crevice Spiders because of their tendency to hide and nest in tight crevices. The male Southern House Spider is the one that we more commonly see, he does not nest, instead he wanders in search of a mate and food. When a male Southern House Spider is approached, he has an unnerving habit of steadfastly approaching anything in its path. He is not aggressive, he is nearly blind, and will often play dead if he feels threatened. The Southern House Spider’s bite rarely breaks human skin.

Orb Weaver Spiders

Orb Weaver Spiders are in the family Araneidae. There are more than 3,500 different species of spiders included in this family. The Orb Weaver Spiders are most easily recognized by the webs they create. The word Orb, meaning circular, tells us that they create large circular webs. The Orb Weaver’s webs closely resemble the stereotypical circular spider web Halloween decoration. The circle is connected with silk in organized grid shaped patterns like the spokes of a wheel. Some species of orb weaver spiders spin webs up to 3 feet in diameter. Orb weavers can repair their webs, but some species consume the web once they have determined to start anew.

The diversity observed amongst Orb Weaver Spiders is astounding. Orb Weavers are rarely found indoors, rather in the woods, around light fixtures, between fence posts, tree branches or bushes anywhere plenty of insects and strong structures can be found. Orb Weavers are nocturnal, creating their intricate webs at night. If you have ever walked out to your car in the morning and been captured by a large web suspended over your porch, it was likely the night time work of an Orb Weaver Spider. Orb Weavers are not dangerous to humans, and many people consider them beneficial as they just may capture that fly before it finds its way inside.

Wolf Spiders

Wolf Spiders are one of the largest spiders in Florida and Georgia, but they do not rely on webs to capture their prey. Instead, they actively hunt for insects to consume. They have excellent eyesight and sometimes wait and pounce on an insect passing by, or they may actively chase their meal. If actively hunting prey, wolf spiders can make their way indoors, but generally they are found amongst the leaf litter and grass outdoors. Wolf Spiders are well adapted to many different environments and thrive in both suburban neighborhoods and open grasslands and fields, vegetation along waterways, and wooded areas anywhere insects are present.

Because Wolf Spiders are active hunters, they do make it indoors. They are large, up to 2 inches in diameter, extremely hairy, and can elicit extreme fear in those afflicted with arachnophobia. They move quickly, like a wolf, but are not considered a threat to humans. They will bite if threatened, but their venom generally only causes mild swelling, redness, and irritation. They are brown and grey with horizontal stripes. Especially in the instance of a bite, they are often mis-identified as a brown recluse.

Wolf Spiders are unique in the way the females care for their eggs and their young. The majority of spider species lay eggs and encase them in a sac that is either left on the web or burrowed in the ground. The female Wolf Spider is unique in that she carries her eggs underneath her body. When the eggs are ready to hatch, she helps them by tearing open the sack. The Wolf Spider spiderlings stay with the mother for a few weeks, hitching a ride on her back.

Huntsman Spiders/Banana Spiders

The Pantropical Huntsman Spider, commonly called the Cane Spider or the Banana Spider is often found in the tropical environment of Florida and the coastal areas of Georgia. They are sometimes referred to as Banana Spiders because they are commonly found in shipments of bananas from the tropics. The Cane Spider is the local term for this spider in Hawaii.

Adult Huntsman Spiders have a leg span ranging from 3 to 5 inches. They are brown in color with tan markings. Like most other spider species of this color and size, the Pantropical Huntsman Spider is often confused with a large Brown Recluse Spider. It can be distinguished visually by its flattened body shape and black spots on its legs.

Huntsman spiders do not make webs, rather they quickly pounce on peri-domestic insects and inject venom with their strong jaws. The Huntsman Spider is well adapted to living closely with humans but is not tolerant of cold weather. This tropical species tends to make its way indoors in the winter, or may be found in greenhouses and sheds to escape the cold. Indoors, the Huntsman Spider may be found under furniture or cabinets, behind pictures, or in closets. If threatened or trapped, the Huntsman Spider will bite, but it is rarely more serious than localized pain and swelling.

Jumping Spiders

Jumping Spiders, or spiders of the Salticidae family, are the largest family of spiders with over 6,000 species. Some jumping spiders, such as the peacock spider, boast a variety of bright colors and unique patterns. Amongst jumping spiders we see bright fluorescent greens, turquoise, reds, and yellows. Jumping spiders do not build webs, rather they jump on their prey. Named for their jumping abilities, most jumping spiders can jump several times the length of their body. An internal hydraulic pressure system allows for this impressive physical feat. They can change the pressure of the fluid within their bodies, enabling this long jump. Before they jump, many species of jumping spiders tether a filament of silk, so that he can find his way back to his nest after the long jump.

There are 2 species of jumping spiders in Florida, the Gray Wall Jumper and the Pantropical Jumper. Both are medium to large sized spiders, adults ranging from 8-12 mm in length. Jumping spiders are harmless to humans, but if bit by a larger jumping spider, the bite will be locally painful. As these spiders do not make and abandon unsightly webs, rather simply eat mosquitos, flies, roaches, and ants, most people do not consider them a pest.

Brown Widow

Brown widow spiders are a spider species of some concern that is present in the southern United States. Brown widow spiders vary greatly in their colorings, female may be white, grey, dark brown, light brown, or nearly brown. Lighter colored brown widow spiders have clearly defined dark banding around their legs. In darker colored brown widow spiders, a yellowish-orange hourglass shape may be visible as opposed to the bright red marking of the black widow. Brown widow spiders are web builders and may commonly be found in eves of buildings, ledges or wooden fences.

Like all spiders, Brown Widow Spiders are venomous. The male brown widow is not a threat to humans as his fangs are too small to pierce vertebrates’ skin. The female Brown Widow can bite humans and possesses a potent neurotoxin. However, when she bites, the amount of venom injected is less than the Black Widow. In addition, Brown Widow spiders do not defend their webs and almost never bite. In laboratory conditions, when the Brown Widow spider was persistently provoked, she first retreated, then played dead. Despite their powerful venom, Brown Widow Spiders would rather play dead than attack a human. Considering the high numbers of Brown Widow Spiders in some areas, a Brown Widow bite is quite rare.

Black Widow

Black Widow spiders earned their name from the observation that they eat their mate once she has no further use for him. While many species of spiders eat their mates after copulation, the female black widows seem to do it more often in crowded lab conditions than in the wild.

The Southern Black Widow Spider is found all across the southern United States and as far west as Texas. Black Widow spiders are a glossy black and the females have a characteristic bright red hourglass figure on her abdomen. The female Black Widow is typically 3.75 – 5 cm in length, including her legs. The male Black Widow is smaller than the female, and does NOT have the red hourglass figure, however he may have bright red spots on his abdomen.

Outdoor habitats for Black Widow spiders include rock and wood piles, hollowed out tree stumps, and even rodent burrows. Black Widow Spiders are much more likely to bite when disturbed than the Brown Widow Spider. Wear gardening gloves when moving rocks or wood piles. Most spider bites occur because the spider’s environment has been disturbed. Special care should be taken when working in the shed or a barn. Shake out gloves and shoes that have been stored outdoors.

Despite the powerful venom, death from a Black Widow spider in the United States is rare. In fact, a 2011 journal article published in the Permanente Journal, states that there are 3 documented cases of a widow bite causing human death, 2 in Madagascar and 1 instance in Greece. About 2,500 Black Widow Spider bites are self-reported in the United States each year. Treatment protocols involve administering pain killers, muscle relaxants, and wound care management. These treatments are aimed at providing relief from the symptoms, while waiting for the venom to abate. Antivenom is available, but it is sparingly utilized for fear of hypersensitivity.

Brown Recluse

As mentioned above there are many species of spiders prevalent in Florida and Georgia that closely resemble the brown recluse spider. As a result, the brown recluse is often “blamed for” spider bites that he is not guilty of. Often when a spider bites, he is not captured. All the victim of the spider bite can say is, “It was a brown spider.” This leads well-intentioned and cautious doctors to assume that it was a brown recluse spider, and they treat it as such.

Entomologists confirm that brown recluse spiders are not widespread in Florida’s landscape. However, they can stow away and inadvertently travel into the state. Confirmed specimens of brown recluse spiders in Florida have only been found in warehouses, vehicles, storage units, and records retention facilities. A single brown recluse spider bite in Florida has been confirmed via a specimen. It was on a naval ship that had recently arrived in Jacksonville, Florida. These confirmed sightings are all transient in nature there is no evidence that these spiders are established in our homes and yards.

For further information on the dreaded brown recluse spider, we have prepared an article specific to the brown recluse spider. https://ngpest.com/how-to-get-rid-of-brown-recluse-spiders/


Possible "Is it dangerous?" fix suggestion?

[edit: thanks for the info everyone! I've learned a lot from you all today, and now I feel I understand more that hobo spiders are indeed likely not dangerous. Here's hoping that more people learn more about these misunderstood spiders, just as I have. Thanks again!>

I noticed in the sidebar, it says:

If you live in North America, there are only TWO types of spiders with the potential to cause serious harm: Brown recluse (a.k.a. fiddleback) - Loxosceles reclusa Black widow - Latrodectus sp.

I was under the impression that there were three dangerous spiders: Hobo Spiders, Brown Recluse, and Black Widow. Could experts tell me if there is a reason Hobo Spiders are not included?

I am frequently told that Hobo Spider, while similar to a Brown Recluse, they are distinctively different spiders. There is a lot of controversy in the Pacific Northwest in regards to misconceptions of Hobo spiders - they are almost always mistakenly identified as Brown Recluse spiders, even though Brown Recluse are not native to this area.

I feel it would be beneficial if Hobo Spiders were included in the list of dangerous spiders, so as to prevent misconceptions and mistakenly identified Hobo Spiders, and perhaps possible dangerous encounters with Hobo Spiders.

Thanks for reading, here is a source for reference: http://www.cdc.gov/niosh/topics/spiders/ Also, more info on Hobo Spiders: http://www.hobospider.com/info/index.html , in the section "What does their bite look like", it says:

In extreme cases where the bite was not taken care of early, skin graft, amputation, and the possibility of bone marrow failure may occur.

[edit #2: I've left my original question above intact, so that in case others have the same misconception about Hobo Spiders as I did, this thread may be referenced. Thanks again!]

I'm just going to get it all out here, tag this page and refer people to this thread in the future.

There is no scientific evidence to support that hobo spiders are any more dangerous than other spiders, including other species of Tegenaria. This myth only exists in the U.S. The spiders are considered harmless in their native Europe, and in Europe there have been documented bites without necrosis.

To establish causality, you need evidence that one thing is associated with the other. In this case, "one thing" is the spider bite, and "the other" is necrosis. A spider bite is established when you see/feel a spider biting and catch it in the act, and subsequently identify the species. There was one documented bite in a Spokane woman who had another medical condition that coincidentally is associated with dermonecrotic lesions. That doesn't count. In another incident, they blamed a spider they found on a railroad track beside the victim's house. Please. When you get a necrotic lesion, you can't just search the neighborhood and blame the nearest arthropod. This is not how science works. Also, these incidents were some 20 years ago. If anything, the population of hobos has increased and spread since then. If the threat is worth warning people about, you would expect evidence that anyone has been bitten - but there isn't any. Not a single instance.

One study in rabbits found that their venom causes necrosis in rabbits (well, in one species of rabbit but not another species). Rabbit physiology is different from human physiology, and several venoms are known to affect some mammals and not others. Furthermore, in that study, the spiders could not even be provoked to bite. The researchers tried their best to piss off the spiders and get them to bite, and they wouldn't. The researchers ended up extracting the venom and injecting it into the rabbits themselves. Thus, the amount of venom administered in a real bite may not be comparable - if you can even get one to bite.

For the spider to be harmless in Europe, but necrotic in the Pacific Northwest, some theories were proposed:

the separate populations evolved different venoms

they carry different microbes that are responsible for lesions or

arachnophobic Americans were quick to latch onto early erroneous reports and repeated them so much they became common knowledge.

Theories 1 and 2 were debunked by Binford, et al, 2001.

Theory 3 is also supported by the fact that physicians in states/provinces where hobos do not exist attribute necrotic wounds to hobo spiders. Hobos get blamed where hobos do not exist, just like brown recluses get blamed even in Alaska, several thousand miles away from any brown recluse.

For more on this topic see:

Bennett & Vetter, 2004 "Erroneous attribution of dermonecrotic lesions to brown recluse or hobo spider bites in Canada."

Gaver-Wainwright et al., 2011 - study showing hobo venom is not hemolytic and contains no pathogenic bacteria.

Vetter et al., 2003 on the distribution of T. agrestis versus where bites are reported.

A good summary of evidence at Utah extension.

And that, my friends, is why we don't list T. agrestis among the "dangerous" spiders on the sidebar.



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