How to Get Rid of Crab Spiders: Effective and Safe Methods

Crab spiders are beneficial arachnids that play a vital role in controlling the pest population. However, some people find them unwanted and would prefer to keep them away from their homes. In this article, we will discuss methods to effectively remove crab spiders from your living spaces, without causing harm to them or the ecosystem.

One simple, yet effective, method to eliminate crab spiders is by using a broom or vacuum cleaner to remove the spiders and their webs. This prevents the spiders from laying more egg sacs, thus reducing their numbers. Another strategy involves keeping your home clutter-free, particularly in areas such as closets, garages, basements, and attics. Spiders tend to thrive in quiet, undisturbed spaces, so decluttering these areas will make them less attractive to the crawly creatures.

Some species of crab spiders, such as Northern Crab Spider and Ground Crab Spiders, can adapt their colors to blend in with their surroundings, making them difficult to spot. In such cases, vigilance and regular inspection of your home can be helpful in identifying and removing them.

Crab Spider Identification

Appearance and Characteristics

Crab spiders belong to the family Thomisidae and are known for their unique appearance. Some key features include:

  • Legs extending sideways, similar to a crab
  • Ability to walk in any direction
  • Varying colors, such as white, yellow, gray, brown, and rusty

These spiders usually have markings on their dull gray and brown bodies 1. A well-known species, the Goldenrod Crab Spider, has the ability to change color from white to yellow, depending on the flower it inhabits2.

Habitat

Crab spiders can be found in various habitats, such as gardens and residential areas3. Ground crab spiders, which belong to the genus Xysticus, prefer to reside in the ground4. On the other hand, species like the Goldenrod Crab Spider inhabit flowers5.

Behavior and Diet

Crab spiders are ambush predators. They wait patiently for their prey, which usually consists of insects like flies and mosquitoes. Their unique sideways walking ability and varying coloration help them blend into their surroundings, making it easier for them to catch their prey.

Here is a comparison table between Ground Crab Spiders and Goldenrod Crab Spiders:

Feature Ground Crab Spiders Goldenrod Crab Spiders
Habitat Ground Flowers
Colors Dull gray, brown White, yellow
Color Changing No Yes5
Common Prey Insects Insects

In conclusion, identifying crab spiders involves examining their appearance, characteristics, habitat, and behavior. Be cautious around these spiders, but remember that they are also essential for pest control in your environment.

Crab Spider Control Methods

Natural Remedies

  • Inspect plants: Regularly check your plants and gardens for signs of crab spiders. Remove them by hand or with a gentle brush.
  • Encourage natural predators: Attract birds, lizards, or other spider-eating predators to your yard by providing shelter and food sources.

DIY Pest Control Techniques

  • Vacuum: Vacuum visible spiders, their webs, and their hiding spots (e.g., corners, under furniture) indoors.
  • Seal gaps: Fix any cracks or gaps in your home to prevent spider entry.
  • Reduce clutter: Limit hiding places by keeping clutter and debris to a minimum.

(example not needed)

Method Pros Cons
Vacuuming Easy, quick, chemical-free Not effective for hidden spiders
Sealing gaps Prevents reentry, long-lasting Can be time-consuming, may miss gaps
Reducing clutter Limits hiding places, overall tidiness May not eliminate all spiders

Professional Pest Control Services

Trusted companies like Truly Nolen and 4 Seasons Pest Control offer:

  • Satisfaction guarantee: They ensure you’re satisfied with the service.
  • Unlimited callbacks: Professionals will return as needed for additional treatments.
  • Thorough assessment: Complete evaluation of your home’s needs based on square footage.

Avoid making exaggerated or false claims.

Preventing Crab Spider Infestations

Maintaining a Clean Environment

Keeping your garden clean and free of debris helps in preventing crab spider infestations. Remove any dead plants, fallen leaves, and other debris that may serve as hiding places for spiders, insects, and pests. Regularly trimming plants and maintaining them at a certain height can also reduce the chances of crab spiders setting up webs or nests.

For example:

  • Trim the grass to maintain a height of 3 inches
  • Remove dead plants, fallen leaves, etc.

Sealing Entry Points

To prevent crab spiders from entering your home, inspect and seal any cracks or openings in walls, doors, and windows. Use weather stripping or caulking to seal gaps. This helps keep not only spiders, but also other insects and pests at bay.

Some common entry points:

  • Cracks and openings in walls
  • Gaps around doors and windows

Inspect and Treat Plants

Regularly inspect your garden plants for signs of spider nests, webs, or infestations. If you spot any crab spiders or their nests, promptly treat affected plants using insecticidal soap or a natural spider repellent.

Pros and cons of insecticidal soap:

Pros Cons
Effective against crab spiders May harm beneficial insects
Environmentally friendly Needs to be applied frequently

Keep in mind that some plants may be more prone to spider infestations, like those with dense foliage or flowers that attract insects. Prevent crab spiders by ensuring you maintain a clean environment, seal entry points, and inspect and treat plants regularly.

Crab Spiders and Humans

Bites and Medical Concerns

  • Crab spider bites are rare
  • Bites are generally harmless to humans

Crab spiders aren’t known to be aggressive towards humans, and their bites are typically rare. However, if bitten, most people experience only mild discomfort, as these spiders aren’t venomous like the brown recluse or other poisonous species.

Benefits to the Ecosystem

  • Crab spiders are natural predators of insects
  • Help control populations of flies and mosquitoes

Crab spiders play a vital role in maintaining the ecosystem by acting as natural predators of various insects. They are especially helpful in keeping populations of flies and mosquitoes under control, which, in turn, benefits humans by reducing the number of disease-carrying pests.

Example:

Crab spiders are often found in gardens, where they prey on pests like tarnished plant bugs, providing a form of biological pest control for plants.

Comparison of Crab Spider Bites and Brown Recluse Bites:

Feature Crab Spider Bites Brown Recluse Bites
Frequency of bites Rare Occasional
Venomous No Yes
Severity of symptoms Mild discomfort Severe in some cases
Medical intervention Rarely needed Often necessary

By understanding the role of crab spiders in the ecosystem and recognizing that their bites pose minimal risk, we can better appreciate their presence and contribution to maintaining a balanced environment.

Other Common Spiders

Black Widow

The Black Widow spider is a venomous species found in various parts of the US. Its bite can be dangerous, but with prompt treatment, the risk of severe complications is reduced. Some identifying features of the Black Widow include:

  • Shiny black color
  • Red hourglass-shaped marking on the abdomen

It’s essential to take precautions around areas where Black Widows are known to reside and seek medical attention if bitten.

Brown Recluse

The Brown Recluse, or Loxosceles reclusa, is another venomous spider indigenous to the US, specifically in the southeast and parts of the Midwest. Often referred to as “violin” or “fiddle-back” spiders, they can be recognized by:

  • Light to dark brown color
  • Dark violin-shaped marking on the head area

Brown Recluses are common in states like North Carolina, also known as the Tar Heel State. If bitten, medical assistance should be sought immediately to minimize potential complications.

Wolf Spider

Wolf Spiders are large, hairy spiders found throughout the US. They are not considered dangerous to humans, and their bites typically cause minor symptoms like swelling and pain. Some distinguishing features of Wolf Spiders are:

  • Size ranging from 0.25 to 1.5 inches in body length
  • Distinct markings in brown, gray, or black colors

Although their appearance may be frightening, Wolf Spiders are generally harmless and help control the population of other, more harmful insects.

Comparison Table

Spider Venomous Bite Symptoms Identifying Features
Black Widow Yes Severe pain, cramps Shiny black, red hourglass on abdomen
Brown Recluse Yes Necrosis, pain Brown, violin-shaped marking on head
Wolf Spider No Mild pain, swelling Large, hairy, distinct brown markings

Footnotes

  1. Ground Crab Spiders | Missouri Department of Conservation
  2. Goldenrod Crab Spider – MDC Teacher Portal
  3. Common Spiders of Missouri: Identification, Benefits, and Concerns
  4. Ground Crab Spiders | Missouri Department of Conservation
  5. Goldenrod Crab Spider – MDC Teacher Portal 2

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Southern House Spider or Male Crevice Spider: NOT Chilean Recluse????? or Giant Crab Spider

 

Big Spider from South Carolina
Dear Bug Man,
Last summer I had a slight infestation of quite large not overly hairy spiders. It seems like I took out about three this size, including the one which ran across my face at 3 am . After jumping from my face, it hit the carpet with an audible thud. We have a very spider friendly attic and had a bit of a spider sized gap on one end of the pull down attic access stair. I’ve since sealed the crack around the door and haven’t seen more of the big guys. This specimen was found trapped in our bathtub. I could actually hear it scratching around on the sides of the tub in an attempt at escape. If I remember correctly the leg span was around 2+ inches… wish I’d put a ruler next to it. I would have done a “catch and release” but its level of activity made me hesitant to let it out of my sight so I dispatched it with a blast of tile cleaner. I just didn’t want this thing running around in my house with my 5 year old daughter if it’s a bad one. Just so you know, with my daughter carefully supervising, I typically catch and release just about every jumping spider, brown house spider, frog, lizard, etc. which manage to make it into our house. Recently, I’ve noticed a good number of very pale off white or cream colored baby spiders with very fine long legs and about this body shape turning up around the house. They are about 1⁄4” in size (leg span) and are very hard to see because of their color. If you identify the attached photo as being something scary, I’ll definitely try to get an image of the little ones and send it along as well. I know you are covered up during this “buggy” time of year, but I hope to hear from you on this one. I’ve yet to be able to positively make a match to the photos I’ve found on the web. Many thanks,
Kert Huggins
Hilton Head island ,South Carolina

Hi Kert,
My what impressive pedipalps your spider has. We believe this is a Giant Crab Spider in the genus Olios. There is a photo on BugGuide of Olios faciculatus that is a near perfect match. The biggest difference we notice is that the legs on your spider seem considerably more spindly. We would love to get another opinion on this identification.

Update: (07/01/2007)
Olios spider or something more dangerous?
I am not a spider expert as you know, and for sure you may want not to post this alarming suggestion until you are a lot more sure about it than I am, but the non-hairy legs and the shape of the legs makes this look like a recluse to me, maybe like a male of the Chilean recluse? (the Chilean recluse is larger than the brown recluse.) I can’t exactly see if there is a violin-shaped mark on the cephalothorax… But take a look at: http://www.doacs.state.fl.us /pi/enpp/ento/loxoscel.html
Susan

Hi Susan,
We did not want to be alarmist about this, but the stated size and the lack of the identifying violin mark stopped us from posting the nagging suspicion that this might be a Recluse. Perhaps it is time to sound the alarm and see if we can get an expert to weigh in.

Update: Male Crevice Spider (07/02/2007)
Hi Daniel,
I managed to get two spider experts (one in FLA and one here in NYC) to weigh in on the scary-looking spider from South Carolina, and the good news is that it is NOT a Recluse at all (and not an Olios either) but a male crevice spider, Kukulcania hibernalis, family Filistatidae. I asked them if I can send WTB their detailed replies. Let you know soon I hope. Arachnologist, Florida State Collection of Arthropods: “Hi Susan, The photo is of a male crevice spider, Kukulcania hibernalis, family Filistatidae, a species often mistaken for a recluse spider. These are common through the Southeast, especially on buildings. I frequently encounter them in my house. Females have a body length of about an inch, are dark charcoal gray in color, and make flat, very sticky, cobwebs in corners, and around windows and doors. While the females can give a painful bite if trapped against bare skin, the net effect is similar to a wasp sting. It doesn?t cause necrotic wounds like a recluse. When I see males wandering around my house, I pick them up and throw them outside. Hope this helps. Best wishes”
Susan

Hi Susan,
We want to give you and the Florida State Arachnologist a great big thanks.

The second Expert ID on SC spider
This from Louis Sorkin, AMNH, some info that might be useful for you Daniel: “Not a Loxosceles species, nor Olios, but could be a male Filistatid of genus Kukulcania. Hard to tell from the photo even though I downloaded it and magnified it, it wasn’t high enough resolution.Also meant to point out that the eye arrangement is not like an Olios at all, which has 2 transverse rows of 4 eyes each, while the Loxosceles has 3 diads of eyes (6 total). Filistatid spider has a concentration of eyes in front third of cephalothorax, so no diads, no discernable transverse rows. Kukulcania males have long legs and slender body compared to females. His palps are also elongated, but hard to really see the tips in photo. Louis”
Susan

(07/02/2007) Big Spider from South Carolina
Daniel,
I was just about to write and ask it the crevice spider was a possibility based on an image in the following link you sent earlier. The flat very stick web confirms it! They are present all around the gable end vents in my attic space. What appears to be bare wood is covered in a very sticky almost film like layer of web. I was concerned about the potential of a type of recluse as we have relatives in Florida and receive boxes from them regularly. We also spent 3 years in Gainesville, Florida while my wife attended U.F. so a stowaway was a possibility. Thank you so very much for the extraordinary lengths you went to make this identification. I will sleep much better tonight!
Kert Huggins

(07/02/2007)
Great detective work by everyone on the male crevice spider! The angle of the image managed to camouflage those incredible pedipalps, which are a hallmark for ID of the males.
Eric Eaton

(07/03/2007)
I have looked around with Google and wanted to also let you know that this spider seems to be most often known as the ‘Southern House Spider’ which makes it sound even more common and even less threatening… Best,
Susan

Letter 2 – Three Green Crab Spiders

 

teensy weensie fluorescent green spider
Hi Dan and Lisa! I found this tiny spider on a neighbors mailbox here in the Chicago ‘burbs. It’s less than 1/4 inch in size and I’m kinda surprised I even saw it. My apologies if I sent this in already. It’s not in my “Emailed Bugs” folder, so I’m not sure. Warm Regards,
Joanne

(06/10/2007) Green Spider
Dear Bugman,
I live in Central Pennsylvania, and while at work one day I seen this amazing green spider on the wall outside. Do you by any chance know what kind it is?
Bobbie Jo

(06/10/2007) spider
I love the face on the tail end. I saw it in chicago
Doug McGoldrick Photograph

Dear Joanne, Bobbie Jo, and Doug
Since you all seem to have submitted the same species of spider on the same day, we decided to streamline our posting job and combine your three letters. You each have photographed a Crab Spider, probably in the genus Misumena, and more than likely a color variation of Misumena vatia.

Letter 3 – Running Crab Spider or Flattie???

 

Subject: I can’t find this guy in any books!
Location: Wichita, KS
October 17, 2012 6:34 pm
Dear Bugman,
Originally I thought this was a crab spider but it doesn’t match any of the pictures I’ve seen. Also, it lays incredibly flat when resting and appears to have feathery, white hairs on it’s back legs. I’m stumped! Thanks for your help!
Signature: Matt

Running Crab Spider or Flattie???

Hi Matt,
Looking at your photos and reading your description, we believe this is a Flattie in the genus Selenops.  See this photo on BugGuide which reports the genus from Texas, Arizona and Florida and notes:  “This genus is found throughout the tropics and subtropics worldwide and can be found in southern parts of the U.S.”
  Since Wichita is in southern Kansas, this is a possibility.  We cannot see any examples on BugGuide with the hairy legs, but this Australian relative on the Brisbane Insect website looks very similar to your spider.  We wish we could make out the eye pattern on your spider.  We would love to substantiate our identification with others.

Running Crab Spider or Flattie???

Correction Courtesy of Eric Eaton:  Running Crab Spider
Daniel:
I believe this is actually a specimen of a Philodromus sp. (“running crab spider,” family Philodromidae).  I think flatties are restricted to the southern U.S. and the tropics.
Eric

I appreciate all of the information! I’m not an expert but after reviewing both pictures, I think it resembles a Flattie more. The biggest difference appears to be size and the coloration on the abdomen. Also, the feathery appendages are different than what I’ve seen online as well. I need to get a better series if pictures and perhaps use a macro lens to photograph the eyes.
Matt
Certified Coloring Book Professional

Thanks for the update Matt.  We would tend to trust Eric Eaton’s opinion, but the photos you submitted are lacking in detail.  A good photograph of the eye arrangement would be helpful.  After Daniel’s book came out, he had a wild idea to do a children’s coloring book.  What do you think?

 

Letter 4 – Unknown Species of Crab Spider from Panama

 

Panama spider
What a great site! And so many knowledgeable experts wading in. Last month (November 2007) I photographed the spider in the attached photo along the Pipeline Road, Panama. The "stalk" it is sitting on is about the size of my index finger, so it is fairly large. We have spiders in Michigan that ambush prey on goldenrod and asters, but they’re much smaller and shaped quite differently. Any ideas? Thanks!
Allen Chartier

Hi Allen,
The spider from Michigan you mentioned is the a Crab Spider, Misumena vatia, also known as a Flower Spider or Goldenrod Spider. We agree that this gorgeous Panamanian species is in the same family, Thomisidae. We will try to properly identify the exact species, but that might be difficult. Right now we will post your letter and image in the hopes that someone can identify the species. Meanwhile, we really need to plant our sugar snap peas and prepare for Christmas Eve dinner.

Daniel,
Thanks very much! Yes, I am familiar with Misumena vatia, as well as Misumenops asperatus, which both occur in Michigan (and I have photos of both). The abdomen of this Panamanian spider also reminds me of our Micrathena gracilis and M. sagittata, but they are smaller and in the orbweaver family (Araneidae), definitely not related. I have many photos on my website, including a lot of insects but so far it is mainly butterflies, dragonflies, and beetles. I haven’t found time yet to put up any of my spiders and other insects.
Allen Chartier
Website: http://www.amazilia.net
Michigan HummerNet: http://www.amazilia.net/MIHummerNet

Letter 5 – Selenopid Crab Spider

 

Flat Spider
Bug Man
We live in central Mexico and these spiders are very common here. They are incredibly fast when they move, but most of the time they are absolutely still. The one pictured is about an inch and a half in diameter and is a very young one. We have seen them much larger, up to about three inches across. If you could help in identifying it we would appreciate it very much. We just call them "Flat Spiders" because they are.
Perry & Katherine

Hi Perry and Katherine,
We believe this is a Selenopid Crab Spider. Our Audubon Guide states: “These rather flat bodied spiders, … live under stones and bark. … When disturbed, they run sidewise, crablike, and hide in a crevice. Mostly tropical spiders, there is only 1 North American genus which occurs in the Southwest.” That genus is Selenops. The Guide describes that genus this way: “These spiders are active in dim light and darkness, seldom by day. They creep forward slowly to reach prey but run sideways much more rapidly. a characteristic of this genus.”

Letter 6 – White Banded Crab Spider

 

What arachnid is yellow & black in CALIF but not a garden spider?
November 4, 2009
What arachnid is yellow & black in CALIF but not a garden spider?
• Your letter to the bugman    I found this arachnid on the head of an acquaintance last week so I flicked it out of his hair with my finger. I looked all over to see where it landed but couldn’t find it. This morning I went out to my truck and it was on my front seat! I’m in Santa Cruz, California.
Please help me identify it.
Thank you, James
Santa Cruz, CA 95060

White Banded Crab Spider
White Banded Crab Spider

Hi James,
Your spider is a highly variable White Banded Crab Spider, Misumenoides formosipes, and it is harmless.  There are several matching images on BugGuide.

Letter 7 – Unknown Spider identified as Running Crab Spider

 

Sunday Morning Spider
April 25, 2010
Found this little one waiting at my desk this morning. It was sitting on top of the scrap of paper that acts as my things to do list, so I happily put off cleaning my desk and checking my e-mail so we could take some spider glamor shots.
I also found what might be an easier way of searching the site. Rather than going through all the blog postings, you can type the following query into google:
site:www.whatsthatbug.com spider
Replace spider with whatever insect you like, and all the lovely photos on the site with that name appear.
I guess it wasn’t that helpful though, as I still couldn’t identify this one. Oh well, maybe you can help. Thanks!
Pete
Portland, OR

Running Crab Spider

Hi Pete,
Our quick web search did not provide a match, so we are posting your unidentified spider in the hope that someone will be able to assist in the identification.  It reminds us a bit of a Lynx Spider, but not enough to provide a match.  Those pedipalps indicate it is probably a male spider, and that supports is diminutive size of less than the diameter of a penny.

Identified as Running Crab Spider by Karl
April 26, 2010
Hi Daniel and Pete:
This looks a Running Crab Spider (Philodromidae), probably a male Philodromus dispar. This is actually a European species that was introduced to North America (I don’t know how or when) and has become established in British Columbia, Washington and Oregon. There are other species of Philodromus in the region but none of them look like a match to me (see bugguide.net). There is also a least one other European species (P. aureolus) that looks pretty much the same to me, but I don’t think it has made it to this side of the Atlantic. Regards.
Karl

Running Crab Spider

Wow, that’s great! My girlfriend is a huge fan of anything with even the slightest reference to ‘crab’, so she’s got something new to sketch. Thank you so much for the detailed response!
Pete

Letter 8 – White Banded Crab Spider

 

strange yellow spider?? Southern CA
Location:  Orange County, CA
October 6, 2010 10:15 pm
Hi!
I photographed this yellow spider on my daughter’s umbrella. Thought it might have changed color to match/blend in? It was exactly the same yellow!
When I blew gently on him, the front legs, which1st appeared to be only single on each side, spread apart and there were two claw-like legs on each side. (see photo)
Very interesting.
He’s living under the eave, undisturbed.
Any help you can give identifying would be appreciated.
Signature:  Thanks, Amy

Crab Spider

Dear Amy,
Your lovely spider is a Crab Spider in the family Thomisidae, and we are quite certain it is the Whitebanded Crab Spider,
Misumenoides formosipes, a common species in Southern California that is well represented on BugGuide as well as being the representative for the family in Charles Hogue’s wonderful book Insects of the Los Angeles Basin.

Letter 9 – Running Crab Spider

 

What kind am I
Location: Middle Eastern Missouri (USA)
March 23, 2011 10:22 pm
I found two of these near the same spot behind my living room couch. At first glance i thought they may be Brown Recluse but a closer look and I 99.9% sure they are not but what are they?
Season: Start of spring
Signature: Tim Cochran

Running Crab Spider

Hi Tim,
Our first inclination is that this looks like a Giant Crab Spider in the genus
Heteropoda, though Missouri is a bit north for us to feel comfortable with that, not to mention that your specimen appears smaller.  The large pedipalps indicates this is a male spider.  We are going to enlist assistance from our readership with this identification.

Running Crab Spider

We also wish the resolution of your image was better because moving in close does not really reveal the eye pattern very clearly.

Running Crab Spider

Eric Eaton provides an identification
Nope, it is a “running crab spider,” family Philodromidae.
Sorry, gotta run.
Eric

According to BugGuide, Running Crab Spiders or:  “Philodromids tend to have the second pair of legs significantly longer than the first pair, which distinguishes them from the similar Thomisid crab spiders. In addition, thomisids have third and fourth legs that are shorter and more slender than the first two pairs of legs, while philodromid legs are subequal in length.”

Letter 10 – Robotic Spiders Hiding in Bathrooms: Terrorist Plot Revealed!!!!

 

Subject: brown spider IN MY TOILET PAPER ROLL.
Location: Western PA
March 27, 2013 12:13 pm
Ok. So this brown nightmare spider fell out of the toilet paper roll this morning, probably because mother nature wants me dead. Can you identify this spider before I do something rash, like call a priest, or perhaps burn the house down? It was brown – it looks darker in the picture because I put it on Instagram (as proof that my house is out to kill me, and to explain to my friends and family why the next time they use my bathroom there will be a bidet in place of toilet paper). Also of note, while there SHOULD NOT be Brown Recluse in our area, there are. My son was bitten in 2009, my neighbor was bitten within days of my son, and my cousin was bitten in May 2012. Please help!
Signature: Cassie

Deadly Bathroom Spider
Deadly Robotic Bathroom Spider

Dear Cassie,
We have just learned about an elaborate terrorist plot that involves robotic spiders that hide in bathrooms among the toilet paper.  When the toilet paper is used and the spider comes into contact with areas of tender flesh, it bites the hapless human and injects a mind control substance much like the zombie venom the Emerald Cockroach Wasp uses on Cockroaches.  The human then does the bidding of the terrorist cell which uses the radio receiver in the robotic spider to set into motion a plan that involves the placing of additional robotic spiders in the homes of friends and relatives.  This will create a veriable army of zombies expected to bring about the downfall of the capitalist and consumer culture we have enjoyed for many years.  It seems western Pennsylvania is ground zero for the attack.  Consider yourself lucky to have avoided this evil plot to take over the world, at least for now.

Update:  April Fools
Eric Eaton provides and ID
Daniel:
The spider in the image is an adult male running crab spider in the family Philodromidae, probably genus Philodromus though I’d need to examine the specimen to be absolutely positive.
Are you sure you want to potentially start another viral spider hoax?  The arachnological community battles enough of those already.  Just sayin’.
Eric

Ed. Note:  April Fools’ Day Joke
While the original letter is true and unadulterated, we found it so amusing we thought we would have a bit of fun with the response.  We did clue Cassie in on our intentions to run this as a prank on our readership and we sincerely hope we haven’t offended anyone.

Here is our original response to Cassie:  “Hi Cassie,  We are working on getting your spider identified, but we got such a chuckle out of your letter that we are planning it to be our April Fools’ Day joke.  We hope to get back to you really soon with an accurate ID as well as a hoax response.”  For the record, male spiders are not considered dangerous and Running Crab Spiders are considered harmless.

hahaha!! thank you! 😀 that’s awesome!
you guys rock!
Cassie

Letter 11 – Russian Crab Spider

 

Subject: Unkonwn green-abdomen spider
Location: Central Russia
September 29, 2013 5:20 am
Hi! Would you be so kind to take a look and identify?
Signature: Alexander

Unknown Spider
Crab Spider

Hi Alexander,
We do not recognize this beautiful spider and we have not had any luck finding a matching image on the internet.  We can tell you that this is a male based on the developed pedipalps.  We suspect this is an Orbweaver, or perhaps a Crab Spider.  Perhaps one of our readers will be able to assist in the identification.

Unknown Spider
Crab Spider

Karl provides an identification
Hi Daniel and Alexander:
It does look like a Crab Spider (family Thomisidae), probably Ebrechtella tricuspidata. It also goes by the synonym Misumenops tricuspidata. Either way, it is the single species in the genus. It is widely distributed, eastern and southern Europe to China, but is apparently uncommon throughout its range.  Several web sites refer to it as the Triangle Crab Spider, but given its range it may have other common names as well. Regards.  Karl

Welcome back Karl, and thanks for the identification.  We were wondering if cooler weather and shorter daylight hours might be providing you with additional time to research some of our unidentified species.

Thank you very much!
You’re doing great job!
Sincerely,
Alexander Ivanov
http://ZooBot.ru

Update from Karl:  October 21, 2013
Hi Daniel. We are still pretty busy here but you are right about the cooler weather and (hopefully) more free time being on its way. Actually, the main reason you haven’t been seeing much from me recently is that we have been having huge issues with internet connectivity. We moved back to the country a few years ago and unfortunately our property is in some kind of cyber dead zone. This summer has been particularly bad, with internet connectivity and speed ranging from poor to non-existent. However, I believe we may have finally defeated all the problems and things are running rather smoothly at this time (fingers crossed). Also, you and your growing flock of helpful readers aren’t leaving many unresolved mysteries anymore. I enjoy seeing the increased interaction and participation. In my spare time I have been working steadily to identify and catalogue all the insect pictures (and spiders, etc.) that I have taken over the years but it has been a slow grind. Not being able to access the internet doesn’t help. I if I ever get caught up it will probably be years from now, but I hope to have a substantial number uploaded to my photo site over the next few months. Good luck and keep up the great work.  Karl

Hi Karl,
Your input is always greatly appreciated.  Please send us a link to your photo site when it is ready for more public consumption.

 

Letter 12 – Thomisus onustus: Crab Spiders eating and mating on Cyprus

 

Subject: Crab Spider with Flesh Fly in Cyprus
Location: Nicosia (Lefkosia), Cyprus
December 6, 2013 2:49 pm
Seems the site submissions might have slowed down a bit so thought I would send you a two-part submission of the same beautiful yellow lady spider on different days back last February (though mistakingly the pictures are titled with 0212 it was 0213).
The first day she had captured what I believe is a flesh fly (which I know because of this site).
What I find amazing is she’s not holding on with her legs.
So, the question is, is there a name for this crab spider?
Part two coming in a moment.
Signature: Curious Girl

Crab Spider Eats Fly
Crab Spider Eats Fly

Subject: Crab Spider with Mate in Cyprus
Location: Nicosia (Lefkoşa), Cyprus
December 6, 2013 2:56 pm
Hi Again Daniel!
This is the second part showing the Beautiful Yellow Crab Spider on her flower in the first picture. But when I looked closely at her I realized she had additional legs encircling her. That’s when I realized she was being courted and I took a lot of pictures (so I have more if you want them). The little guy was all over her, as can be seen in the second picture.
Really amazing the size difference. On the flower next to her too was at least one other gentleman I guess hoping for a chance but not willing to get on the flower yet. I have some pics of him too.
Signature: Curious Girl

Crab Spiders Mating
Crab Spiders Mating

Dear Curious Girl,
Thanks for waiting until our number of submissions declined.  North American winter is our slowest time of the year for identification requests, but that is also the time the Australian, South African and other southern hemisphere submissions peak, but there are not nearly as many as we get during the summer.  Most of our northern hemisphere submissions at this time are for carpet beetles and other household intruders.  Your photos are awesome.  We cannot confirm that the prey is a Flesh Fly, and though your photos say it all, we would love to be able to provide you with a species name for this lovely Crab Spider in the family Thomisidae.  The knobs on the abdomen are quite distinctive, and if this species is like others in the family, color is not an accurate identifying feature as many Crab Spiders are colored so they blend in with their surroundings, which your photos graphically illustrate.  We found a similar looking individual posted to PBase and again her on PBase, but alas, there is no species ID.  There is another unidentified image on TrekNature.  We wonder if this might be the Goldenrod Crab Spider ,
Misumena vatia, which according to Animal Diversity Web, is found in Europe as well as North America.

Crab Spiders Mating
Crab Spiders Mating

Correction Update:  December 8, 2013 7:44 am
I saw the pictures of the yellow Thomisidae spider of which you say it might be Misumena vatia. Of course I am no specialist at all, only generally interested in insects and spiders, but I have seen several Misumena vatia females here in Europe (Germany and other countries) and not one had these two tubercles (if this is the right word). I understand that such tubercles occur in genus Thomisus, and I found a picture of a spider that is similar to those posted by “Curious Girl”, identified as T. onustus:
http://www.treknature.com/gallery/photo155051.htm
Kind regards, Erwin
Signature: Erwin Beyer

Thanks so much for the correction Erwin.  It is greatly appreciated.  Nick’s Spiders of Britain and Europe has some wonderful photos showing various color variations on Thomisus onustus, including a yellow form, and they all have the bumps on the abdomen.  Encyclopedia of Life also pictures a yellow individual that closely resembles the spider photographed by Curious Girl.

Curious Girl Writes Back
Ah well, you snooze you lose :~)
I was going to reply to tell you that I had found the spider name. Of course I needed to be reminded, or prompted by you but, I’ve found if I look up insects of Greece that many of those found on Cyprus will be revealed as they share a similar zoology (?). So, I had found Thomisus onustus as the genus name but the common English name is Heather Spider. Not all that different from Goldenrod.
Ironically, just before I left on my big travel adventure I randomly found a Goldenrod Crab Spider in my bed. An odd place for her I thought. I had seen pictures of them and found them fascinating so hoped to find one someday but really was not expecting one where I found her. That one was white with the pretty pink bands.
Seems the Heather Spider can be yellow (as we see) white, pink, and even partly green.
I wonder though if you noticed that not only does she happened to have what appears to be pollen on her pedipalps but also that her silk seems very yellow as well. She’s also missing a front leg on her right side.
Seems the little ones will eat pollen and nectar if they can’t capture prey. Might help them with their color change miracles.
Good job to Erwin on identifying the spider, and maybe he can find an identification for the wasps from Germany I sent in last year. :~)
Oh, and thank you for the compliments on my pics. When I get the others ready I’ll send a few more to you (if you’d like).

Oh, and the Encyclopedia of Life link has the common Portuguese name for the spider which is “Aranha-florícola-de-tubérculos” which makes me happy because Portugal is my favorite place in the world. This leads to a great picture of a spider guarding her egg-sac.
http://www.flickr.com/photos/luisgaifem/5989104744/

 

Letter 13 – Undescribed Crab Spider from Australia: Sidymella species

 

Subject: Any Idea?
Location: Sydney, NSW, Australia
August 2, 2014 5:13 am
Hey,
I found this 2cm big guy near a salt water river in Sydney, Australia. I have no clue if its a spider/scorpion thing or just a bug or whatever. I am not even sure if there a 4, 6 or 8 legs …
I googled a lot but cant find anything helpful…
(sorry for my english 😉 )
Signature: Ben

Crab Spider:  Sidymella species
Crab Spider: Sidymella species

Dear Ben,
Your English is perfectly fine.  Your confusion is well founded.  Both Spiders and Scorpions are classified in the zoological class Arachnida, the Arachnids, so they share many physical similarities.  Insects and Arachnids, including Spider and Scorpions, are classified together in the phylum Arthropoda, and again, they all share certain physical characteristics.  With that stated, this is a Spider in the order Araneae, and Spiders are identified because they have two body parts, the cephalothorax (combined head and thorax) and abdomen, and eight legs.  This particular Spider is holding its two front pairs of legs together, which makes it a bit difficult to count.  The two front pairs of legs are considerably longer than the rear two pairs, and this is a physical trait shared by Crab Spiders in the family Thomisidae.  Once we got to that level of identification, we turned to one of our favorite sites for identifying Australian Arthropods, the Brisbane Insects and Spiders, where we found a very similar looking Crab Spider identified as being in one of two genera:
Tmarus or Sidymella.  The site author coined the name Peak Crab Spider ” because its abdomen rises to a dorsal peak.  Its two front pairs of legs are much longer than the hind two pairs.”  Scroll to the bottom of the page to see the Peak Crab Spider.  Armed with that information, we found other representatives in the genus pictured on Spiders of Australia, and the closest matches are not yet fully identified, and are given the names Sidymella ZZ477 and Sidymella ZZ592.  Those letter and number identifyers indicate that the Spiders have yet to be described in a published paper at which time they can be given species names by the describer.  This is a very exciting posting for us and we are featuring it in our scrolling featured posting bar.

Letter 14 – Running Crab Spider

 

Subject: ID: Happy face Ebo species?
Location: San Mateo County, CA
April 15, 2015 4:54 pm
Hi,
I’m wondering if you might be able to identify this Ebo to species – I found it a few days ago in San Mateo, California. There are very few Ebo photos online and barely any keys, but there are only eight species to choose from in North America. I am not an expert, just the finder/photographer, but I’d love to know if possible.
Here’s the photo link on BugGuide: http://bugguide.net/node/view/1055794#1870794 And my original post of this spider on iNaturalist, which includes better geodata and an alternate/enhanced photo: http://www.inaturalist.org/observations/1392763
Thank you so much for doing this – !
Signature: – Robin Agarwal

Running Crab Spider
Running Crab Spider

Hi Robin,
Now that the contributors of BugGuide have determined that your image is a Running Crab Spider in the genus
Ebo, you may get additional assistance there as well as on our site.  We are posting your image and we hope our readership can contribute to your request.

Hi Daniel,
As of yesterday, it was identified as Ebo evansae by Darrell Ubick, Arachnologist at the Cal Academy of Science.
Thanks for your help on this!
– Robin

Thanks for letting us know Robin.  We are updating our posting.

Letter 15 – Running Crab Spider, we believe

 

Subject: Spider in Hydrangea
Location: Texas
May 14, 2016 9:06 pm
What kind of spider is this? is it venomous or harmful?
Thanks
Signature: Jacob Chapman

Running Crab Spider, we believe
Running Crab Spider, we believe

Dear Jacob,
We believe this is a Running Crab Spider in the family Philodromidae, and possibly in the genus
Philodromus which is well represented on BugGuide.  According to BugGuide, the family members can be recognized because they:  “tend to have the second pair of legs significantly longer than the first pair, which distinguishes them from the similar Thomisid crab spiders. In addition, thomisids have third and fourth legs that are shorter and more slender than the first two pairs of legs, while philodromid legs are subequal in length.”  While Running Crab Spiders do have venom that they use to incapacitate prey, they are not considered dangerous to humans.  The long first appendages, known as pedipalps, indicate your individual is a male.

Letter 16 – Running Crab Spider

 

Subject: Two bugs
Location: Wyoming
August 11, 2016 9:48 am
I have two bugs, one that appears to be a spider and one that appears to be a lady bug. The spider looking bug was found in the bathroom and the lady bug was found outside. I live in Wyoming where our climate is cold in the winters which are almost 8 months of the year and warmer summers for the rest of the year. I hope you can help me identify these bugs.
Thank you.
Signature: Liz Hensley

Running Crab Spider
Running Crab Spider

Dear Liz,
We identified your spider as a Running Crab Spider in the genus
Ebo, thanks to BugEric where it states:  “Philodromids are identified rather easily by the fact that their second pair of legs is longest.  The genus Wbo takes this to an extreme, as that second leg is at least twice as long as all the others.  Their “wingspan’ must be the greatest for their size of any spider in North America.  Their body size is small, averaging between two and six millimeters depending on the species, and skewing towards the lower end of that spectrum.”  According to BugGuide:  “The Ebo characteristic trait is the elongated second pair of legs, which can be more than twice as long as the other legs.”  BugGuide recognizes at least two species in the genus in Wyoming, though BugGuide data does not report any.  Your beetle image, which we are not posting, is a Leaf Beetle in the genus Calligrapha.

Letter 17 – Whitebanded Crab Spider in Mount Washington

 

Subject:  Superb spider on my milk weed
Location:  Mount Washington, Los Angeles, California
October 16, 2016 2:21 PM
Hi Daniel,
I can’t believe how long it has been since we spoke.  …
I think you are going to like my yellow and black spider on the bright milkweed.
See you soon.
Hug,
Monique

Whitebanded Crab Spider
Whitebanded Crab Spider

Dear Monique,
This beautiful Crab Spider looks like one of many color variations possible for a female Whitebanded Crab Spider,
Misumenoides formosipes, which we identified thanks to this BugGuide image.  According to BugGuide:  “The identifying characteristic, according to Florida’s Fabulous Spiders, is a white ridge on the spider’s face below the eyes. Can be either white or yellow. Most sources say this is a response to its surroundings, but I did find one claim that color depended on whether the egg was laid on a yellow or white-flowered plant.”  Crab Spiders in the family Thomisidae do not build webs to snare prey.  They are often found perched on blossoms where they wait for prey to be attracted to the nectar, ambushing the unsuspecting pollinating insects.

Letter 18 – Tailless Whipscorpion from Nicaragua

 

Subject:  Spider in Nicaragua
Geographic location of the bug:  Matagalpa, Nicaragua
Date: 10/02/2017
Time: 04:03 PM EDT
We found this spider already deceased and decided to take a picture and try to identify it in case we find more of them.
How you want your letter signed:  Dalton Bragg

Tailless Whipscorpion

Dear Dalton,
This is a Giant Crab Spider or Huntsman Spider in the family Sparassidae.  There is a similar looking image on Arácnidos de Centroamérica.

Correction courtesy of Karl
Hi Daniel. I think this is actually a Tailless Whipscorpion (Amblypygi). Regards, Karl

Thanks for the correction Karl.  Now that you have brought this to our attention, we agree with you that this is a Tailless Whipscorpion.  They look much more distinctive alive.

Letter 19 – Slender Crab Spider

 

Subject:  Stick bug id
Geographic location of the bug:  Antioch, CA, USA
Date: 06/24/2018
Time: 03:44 PM EDT
Your letter to the bugman:  Hi, I occasionally have these cute bugs around my property and am wondering what they are.
How you want your letter signed:  Thanks, Kim

Slender Crab Spider

Hi Kim,
We turned to the Natural History of Orange County site to view Spider thumbnails and we thought your individual resembled the Running Crab Spider in the genus
Tibellus that was pictured there, but alas, we were basing that on a single image.  We then searched the genus on BugGuide and we believe you have a Slender Crab Spider, Tibellus chamberlini.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

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  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

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