Pseudoscorpions, often overlooked, provide a variety of benefits to humans. These tiny arachnids, which resemble scorpions without a tail or stinger, are natural predators of a range of household pests. Undoubtedly, their presence can be a boon in controlling these unwanted visitors.
These small creatures, which grow up to 1/4 inch or less in length, help keep the ecosystem balanced by feasting on insect larvae, ants, dust mites, and small flies. With no harm to humans, pseudoscorpions can be considered as beneficial allies in maintaining a healthy environment within our living spaces.
Overview of Pseudoscorpions
Arthropods and Class Arachnida
Pseudoscorpions are small arthropods belonging to the class Arachnida, along with other creatures like spiders, scorpions, and ticks. Some characteristics of arachnids include:
- Having an exoskeleton
- Possessing four pairs of walking legs
- Respiration through spiral trachea or book lungs
Arachnids play a significant role in maintaining ecosystems by controlling insect populations and serving as food for other animals.
Order Pseudoscorpiones
The order Pseudoscorpiones contains over 3,000 species of pseudoscorpions. These fascinating creatures are typically:
- Very small, ranging from 2-8 millimeters in length
- Possessing pincer-like appendages called pedipalps, similar to scorpions
Pseudoscorpions can be found in a variety of environments, such as soil, leaf litter, and even among books, hence their nickname “book scorpions”.
Relation to Scorpions and Spiders
Pseudoscorpions are related to both scorpions and spiders, but they differ in several ways. Here is a comparison table highlighting some key differences:
Feature | Pseudoscorpions | Scorpions | Spiders |
---|---|---|---|
Body Shape | Teardrop-shaped | Elongated | Segmented |
Pincer-like Arms | Present | Present | Absent |
Venomous | Yes | Yes | Some |
Web-building | No | No | Yes |
One of the most notable differences is that pseudoscorpions lack the elongated stinger-tail characteristic of true scorpions. However, they do possess venomous glands in their pincers, which they use to subdue small prey like insects and mites.
In conclusion, pseudoscorpions are unique arachnids that play a valuable role in controlling other small arthropods, contributing to the balance of our ecosystems.
Physical Characteristics of Pseudoscorpions
Size and Appearance
Pseudoscorpions are tiny arachnids that are usually only about 1/4 inch long. Their bodies are:
- Flattened
- Teardrop or pear-shaped
- Reddish or brown in color
Pincers and Pedipalps
These miniature creatures have two very long, armlike pedipalps that end in pincers. These pincers are:
- Similar to those of scorpions
- Highly functional for grabbing prey
- Relatively large in comparison to their overall size
Legs and Movement
Pseudoscorpions possess eight walking legs that help them navigate their environment. Key features include:
- Efficient crawling and ambushing abilities
- Use of legs for sensing vibrations in their surroundings
- Exhibiting quick bursts of movement when attacking prey
Size Comparison Table:
Pseudoscorpion | Scorpion | Spider |
---|---|---|
1/4 inch | Up to 9 inches | Various |
In summary, pseudoscorpions have certain physical attributes such as size, pincers, and legs that distinguish them from other arachnids. Knowing about their physical characteristics could help to better understand how they might be helpful to humans.
Habitat and Behavior
Common Habitats
Pseudoscorpions can be found in various environments, but they typically prefer damp areas. Some examples of their habitats include:
- Mulch
- Leaf litter
- Stones
- Tree bark
- Indoors, sometimes near books (source)
An interesting fact: some species are native to the Canary Islands!
Food and Diet
These tiny arachnids are not only harmless to humans but beneficial as they feed on pests such as:
- Larvae of clothes moths
- Carpet beetles
- Ants
- Dust mites
- Small flies
- Booklice (source)
Mating and Reproduction
Pseudoscorpions perform an intricate mating dance to reproduce. The process often involves the male depositing a sperm packet called a spermatophore, which the female collects. After mating, females lay disk-shaped cocoons containing their eggs. The young reach maturity after a few molts, resulting in adult pseudoscorpions that can live for several years (source).
Aspect | Pseudoscorpion |
---|---|
Class | Insecta |
Mating Dance | Yes |
Reproduction Method | Spermatophore |
Habitats | Damp areas |
Native Location | Pennsylvania, Canary Islands |
Lifespan | Several years |
Pseudoscorpions and Human Interaction
Harmlessness and Benefits
- Pseudoscorpions are harmless to humans, presenting no danger in homes.
- They are beneficial as they eat pests like larvae, ants, dust mites, small flies, and booklice.
Example: Pseudoscorpions can reduce larvae of clothes moths and carpet beetles in homes.
Control and Physical Removal
- In case of infestation, use non-chemical control methods.
- Regular vacuuming helps to remove pseudoscorpions easily.
Pros:
- Minimal harm to the environment.
- Safe for humans and pets.
Cons:
- Might not be completely effective.
- Requires persistence and daily attention.
Conservation Efforts
- Pseudoscorpions contribute to maintaining a balanced ecosystem.
- Encourage biodiversity by protecting their habitats.
Comparison Table
Feature | Pseudoscorpions | Harmful Pests |
---|---|---|
Effect on Humans | Beneficial | Harmful |
Lifespan | Several Years | Variable |
Physical Danger | None | Varies |
Conservation | Necessary | Control |
Pseudoscorpions play an essential role in controlling harmful pests in homes while being completely harmless to humans. Therefore, efforts made to conserve their habitats, encourage biodiversity, and use non-chemical methods to control their population are all crucial aspects of managing the interaction between pseudoscorpions and humans.
Predatory Role of Pseudoscorpions
Preying on Insects and Arachnids
Pseudoscorpions, also known as false scorpions or book scorpions, are small predators that play a significant role in controlling the populations of various insects and arachnids. These tiny creatures are known to prey on:
- Ants
- Mites
- Ticks
- Booklice
- Small flies
- Clothes moth larvae
- Carpet beetle larvae
For example, the house pseudoscorpion specializes in preying on clothes moth larvae and carpet beetle larvae, protecting our clothes and carpets from damage.
Pseudoscorpions are venomous, using their pincer-like pedipalps to inject venom into their prey. This venom helps in external digestion of the prey, making it easier for pseudoscorpions to consume their food.
Importance in Ecosystem
Pseudoscorpions are important predators in many ecosystems, especially in gardens where they help control pests. They protect plants by preying on harmful insects and other invertebrates. Their predatory role can indirectly benefit humans, as they keep the balance of these populations in the ecosystem. Moreover, pseudoscorpions are known to engage in phoresis, a form of symbiotic relationship in which they hitchhike on larger arthropods, like beetles or flies, to get to new habitats.
Here is a comparison table of pseudoscorpions and true scorpion species:
Feature | Pseudoscorpions | True Scorpion Species |
---|---|---|
Size | 2-8mm | Up to 20cm |
Venom | Used for external digestion | Used for immobilizing prey and protection |
Sting | No sting or tail | Have a stinger at the tip of the tail |
In conclusion, pseudoscorpions play a vital role as predators preying on insects and arachnids, maintaining a balance in various ecosystems. Their presence helps control pests in gardens and households, ultimately providing indirect benefits to humans.
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 – Pseudoscorpion
Scorpion looking thing.
Location: Monee IL
November 17, 2010 8:56 pm
Hi Bugman. This is the 3rd one of these little guys i have found in my bathroom it has always been on the wall. he is no bigger than 4mm total. He looks kinda scary but im sure he’s harmless. Thanks for your help.
Signature: Brian
Dear Brian,
The Pseudoscorpion got its name because it looks like a Scorpion, but it is not a Scorpion. It has no stinger nor does it have venom. You are correct that it is harmless. Pseudoscorpions are able to capture large prey with those animatronic-like pedipalps. Pseudoscorpions are also capable of phoresy, an activity by which they hitch rides of off other creatures, often flying creatures. We have numerous images in our archives of Pseudoscorpions engaging in phoresy.
Letter 2 – Pseudoscorpion
Subject: Tiny with large pinchers/antannae
Location: Rhinelander, WI
December 30, 2012 10:24 pm
I found this on the wall in a cabin in northern Wisconsin. I was struck by the large pincer/antannae-like things in front. It was about 1-2mm minus the long things. Does anyone have any idea what it is? I don’t know much about bugs, but no one in my family had ever seen anything quite like it before. Thanks!
Signature: KO
Dear KO,
This is a harmless Pseudoscorpion.  Pseudoscorpions are not considered Household Pests. They are generally outdoor creatures, but since they are so small, they are rarely noticed outside. Only when they enter homes do they become more visible. They can survive indoors where they feed on a variety of unwanted Household Pests like cockroaches and other undesirable intruders, so they can be considered beneficial. Unlike their namesakes, Pseudoscorpions do not possess venom and they pose no threat to humans, pets or household furnishings.
Thanks for taking the time to reply! Happy New Year!
Letter 3 – Pseudoscorpion
Subject: Small bed bug
Location: Winnipeg Manitoba
October 17, 2012 8:12 pm
Hey! did a google search and you guys came up. Found a couple of these guys in our bed the other day, was under the impression bed bugs were very small. Doesn’t seem like a flea either. i have know idea. There about as big as a small woodtick, about a quarter as big as your pinky nail. Very flat. We saw about 6 of them. Any help would be awesome, thanks!
Signature: Trevor Johnson
Hi Trevor,
This is a harmless Pseudoscorpion, and since they are predators, they will feed upon Bed Bugs. We would urge you to tolerate their presence and hopefully they will keep your bed and home free of unwanted pests.
Letter 4 – Pseudoscorpion
Scorpion Tick?
Location: Mt. Bethel, PA
November 10, 2010 7:16 pm
My daughter found this odd looking tick-like bug in the bathroom.
Signature: Chris
Hi Chris,
Though your photograph is little more than a silhouette, the outline of the harmless Pseudoscorpion is unmistakable. Pseudoscorpions are frequently mistaken for ticks. Pseudoscorpions are also frequently found inside homes where they prey upon unwanted visitors. They possess no venom so they are perfectly harmless.
Letter 5 – Pseudoscorpion
Subject: Small Scorpion? In Ohio? On my work bench? Creepy!
Location: 41.256194,-83.006687
July 5, 2013 5:23 pm
Hey! I spied this little guy when working outdoors on my portable workbench. About a quarter of an inch long. Looks to me like a whiptail scorpion but no whip?
Signature: Tony Schacher
Hi Tony,
Like Scorpions and Whipscorpions it resembles, this Pseudoscorpion is an Arachnid, but unlike Scorpions, it does not have any venom. Pseudoscorpions are found in many parts of the world. They are perfectly harmless predators and they do not get much larger than the individual you encountered.
Upon seeing my photo upload on facebook my Daughter identified it as a chernetid, or “pseudoscorpion”
Letter 6 – Pseudoscorpion
What the heck is this?
January 29, 2010
This bug was floating in my water cup, I almost drank him. I thought it was a “crab” spider, then he unfurled two long front limbs with claws that resemble those of a scorpion. I’ve never seen anything like this around here. Also strange: it’s the dead of winter (January), temperatures are almost down to the teens outside, so I’d have thought most everything is hibernating or dead. Please tell me what this is! I have him in captivity, he’s alive.
Thank you, David Obal
Central NJ
HI David,
Pseudoscorpions, like the one in your photos, are perfectly harmless because they don’t have venom. Pseudoscorpions are often found inside the home where they will prey upon small insects.
Letter 7 – Pseudoscorpion
some kind of pseudoscorpion??
Hey Bugman!! I love LOVE your site it’s awesome! 🙂 My name is Mischa and I’m 14 years old. I found this bug in my house. It’s not new, I’ve seen it before, but I’m not really sure what it is… It’s about 2 mm long. I live in New-Brunswick, Canada. I would really appreciate if you could identify this for me, I quite like this little bug!! Thanks soo much, keep up the good work!!
Mischa, NB
Hey Mischa,
You did a great job of getting that photography of your Pseudoscorpion through the magnifying device. Though there are different species of Pseudoscorpions, we aren’t prepared to do an exact species identification.
Letter 8 – Pseudoscorpion
Finally something in return!!
Location:Â Wellington, Colorado
June 25, 2011 5:26 pm
Dear WTB,
I have been following for a while and we have used it to identify a few interesting insects. Being a biologist, Ichthyologist, I love biology. Most of the bugs I find, I know already, but I have something in interest for you. Today, 25 June 2011, I just found our first Pseudoscorpion in Wellington, Colorado, USA.
I have a lot of macro photos, digital in JPEG format that I would like to share with you. Some of the photos have a scale (mm) and some with UV blacklight (personal interest in trying to find scorpions) trying to see if they glow like scorpions.
Please email me and I’ll return with about 10 to 12 pics of closeups of the pseudoscorpion.
Thanks for all the work you do and I love the bug carnage as well as the identification.
You will also notice a red scale across the bottom of some of the pictures. This is a ruler and the increments are millimeters. This little guy was approximately 7 to 8 mm in lenth.
Enjoy and if there are any bugs in my area that are of interest for photography, please let me know.
Signature: Sean Seal
Hi Sean,
Thanks so much for sending your photos. It is interesting to learn that Pseudoscorpions do not glow under UV light the same way that regular Scorpions glow. Phenomena like glowing under ultraviolet light might be evidence that certain creatures are able to “see” under different conditions, though this is purely conjecture. Pseudoscorpions are harmless predators that are frequently mistaken for ticks by many people.
Letter 9 – Pseudoscorpion
Odd looking bug with odd pinchers
April 24, 2010
I found this bug earlier this evening in our bedroom (kinda scary) but I have never seen anything like this before. The body size is about 3mm. Each extended arm has 2 pinchers on it. When it’s in defense, it backs up really fast and tucks pinchers in. Can you help me out? Thank you!!
SLJ
South Dakota
Dear SLJ,
Your diminutive visitor is a harmless Pseudoscorpion. They are often found in homes around the world where they will help rid the domicile from unwanted insects.
Letter 10 – Pseudoscorpion
Pseudo-scorpion?
June 11, 2010
I found this bug under my husband’s work shirt in the laundry room. At first I thought it was a tiny spider. After I saw the claws, I thought it was some type of tick. I think it’s a pseudo-scorpion. My question is, are there more? Do you think it could have carried itself in on my husbands shirt or do you think there could be a family living nearby?
Thanks for any info you can provide.
Kathy
Northeastern Ohio, June 10, 2010
Hi Kathy,
Pseudoscorpions are not social creatures. They are solitary hunters, but we would wager this Pseudoscorpion has siblings somewhere.
Letter 11 – Pseudoscorpion
What is this bug?
Subject: What is this bug?
Location: Found in cupboard, came out of old egg dying box.
April 24, 2011 6:22 pm
I found this bug when I was getting some old egg dying stuff out it is April in the Spring time. I sat the carboard box on the table and it came crawling out. I put it in a baggie and was trying to find out what it is…no luck. I do hope you guys can help me.
Signature: Miss Rebecca
Our Automated Response:
Thank you for submitting your identification request.
Please understand that we have a very small staff that does this as a labor of love. We cannot answer all submissions (not by a long shot). But we’ll do the best we can!
Hello,
I am glad to see I recieved an email back so quickly to at least inform me you have noticed I submitted my bug. I do thank you but I actually finally got the research I was looking for and found out what it was. So, please do not feel the need to have to research and send me information. Thank you again for your time and for the great website. It is very interesting to look through it all.
Have a Great Day!
Dear Miss Rebecca,
People don’t usually respond so politely to our automated response. This is a harmless Pseudoscorpion. It is a fierce, though tiny predator. We hope your eggs turned out pretty.
Letter 12 – Pseudoscorpion
Bug ID
Location: North Eastern Illinois
July 22, 2011 6:10 pm
This little guy (or girl) was found in a home in a wooded area of North-Eastern Illinois (Lake County). He (or she) is only big enough to sit on your pinky nail, and has a plump, elongated and segmented abdomen, apparently six legs not including two dispropotionately large front pincers. There appear to be two antenae protruding from the head, but those may be an additional set of legs. Coloration is black or deep brown, yellow or white striping at the segment seams, and on the belly. The pincers and legs appear to be red-ish.
Hope you can work with that and the picture!
Signature: K-Dizzle
Dear K-Dizzle,
This is a harmless predatory Pseudoscorpion. It will not harm your or your pets (unless your pets are small insects) and it will not damage your home.
Pseudoscorpions actually do secrete venom from the pedipalps, although it is completely harmless to humans and so not very important to KO.
Can you provide us with an internet link on the venom issue?
Here’s one. http://seagrant.uaf.edu/marine-ed/curriculum/images/stories/kindergarten/pseudoscorpion.pdf
The venom is relatively weak and can usually only bring down prey the pseudoscorpion’s size or smaller. Some pseudoscorpions have a degree of social behavior because they can team up to subdue larger insects.
Thanks so much for providing this information. We will be sure to use this in future responses while trying to alleviate the fears of folks who encounter harmless Pseudoscorpions.
A Kauai pseudoscorpion tattooed on my leg! Pretty cool arthropod!
I found 2 in my bed, I live in central ab. Canada, how did I get them? Only new foreign object is a house plant.
They may have come in from outdoors.
Just found one of these little buggers on bathroom floor in Belen, NM. Are these found throughout the US?
yes. they are harmless.
Can they do any harm with those pincers? How can I induce these beneficial little creatures to share my living space with me? I don’t use professional or conventional extermination but instead would like to keep my home free of pests naturally by encouraging harmless predator bugs to take up residence. I hate chemicals and generally abide by the “live and let live” rule but I’m sure even What’s that bug? will agree that some species of insect are better when found outside. I see no problem in allowing harmless predators to indulge in their natural food source within my walls as long as I’m not likely to wake up and find one sitting on my nose, lol.
Pseudoscorpions are perfectly harmless. Though they would naturally be found outdoors, we rarely if ever receive images of Pseudoscorpions in a natural environment, yet we receive numerous images of Pseudoscorpions from inside homes, leading us to believe they have adapted quite nicely to cohabitation with humans.
was going to take a shower and one of those fell from the ceiling freaked me the hell out
If u find the Pseudoscorpion in your bread flour then the flour should be tosses out right?
Sift the flour before using.
I found one in my house in Minnesota where do these typicaly live?
Most of our reports come from the northern parts of North America, like Minnesota, and most of our reports are interior sightings, like yours.
How very cool ! I have often wondered what this bug was !
Can you tell me does it eat fabric , like a moth ?
No. It is a predator.
I found one in my nose?? I woke up one morning knew some thing was different blew my nose and this came out
found one in Alaska, if it is not a scorpion then is it a spider or a mite?
None of the above. They are Arachnids in the class Arachnida, as are all Spider, Scorpions and Mites, but they are further classified in their own order, Pseudoscorpiones. See BugGuide for a breakdown of the different orders within the class.
thanks so much for the intel – am in tick country so freaked by wee little brown specs that move!
Found one on the side of my son’s tent after he came home from Tahosa Boy Scout Camp today (near Ward, Colorado). I thought it was a tic, but it had these long pincer things, and I thought, yikes tics are evolving. Killed it and photographed it under a loop, then found this fabulous website, and now know the truth.
I just found one on my bedroom wall..sized it up for a minute then killed it.. then found my way here lol
Found one while reading a book at Wasagaming (Riding Mountain National Park) Manitoba June 30, 2019. These things seem to be ubiquitous but it is the first I’ve ever seen. Is there a lot of variety in this order?
The order has significant taxonomic diversity.