Devil’s Coach Horse Beetle: Quick Facts and Essential Insights

The Devil’s Coach Horse Beetle is a fascinating and beneficial insect commonly found in gardens, meadows, and woodland areas. This intriguing beetle has some unique features and behaviors that set it apart from most other beetles.

One key characteristic of the Devil’s Coach Horse Beetle is its black, elongated body, measuring about an inch in length. It belongs to the rove beetle family and is known for being a beneficial predator, as both its larvae and adult forms feed on a variety of pests, including slugs and aphids.

A distinctive feature of this beetle is its defensive stance, where it raises its abdomen, mimicking a scorpion when threatened. Despite its menacing appearance, the Devil’s Coach Horse Beetle does not possess a sting and is generally harmless to humans.

Basic Information

What Is a Devil’s Coach Horse Beetle

The Devil’s Coach Horse beetle (Ocypus olens) is a species of beetle belonging to the Staphylinidae family, commonly known as rove beetles.

Characteristic Features

Features of Devil’s Coach Horse beetle:

• Black body with elongated shape
• Adults grow up to 1 inch (25mm) long
• Fierce looking jaws, called mandibles
• Capable of emitting a foul-smelling secretion
• Raises tail when threatened, similar to a scorpion

Relation to Rove Beetles

The Devil’s Coach Horse beetle is part of the rove beetle family, Staphylinidae, which consists of over 60,000 species worldwide. As a rove beetle, its characteristics include:

• Long and flexible abdomen
• Short elytra (wing covers)
• Abdomen extends beyond elytra
• Fast running and active predator

Comparison Table: Devil’s Coach Horse beetle vs. Other Rove Beetles

Habitat and Distribution

Geographical Distribution

The Devil’s Coach Horse Beetle is native to Europe and can be found in various countries including the UK and Ireland. It has also been introduced to North America and North Africa, but remains less widespread in these regions.

Habitats Preferred by the Beetle

The Devil’s Coach Horse Beetle prefers a variety of habitats, such as:

• Woodland: They are commonly found in woodlands, particularly in damp and shaded areas.
• Grassland: Open grasslands are also suitable as it provides a good hunting ground for these predatory beetles.
• Hedgerows: These habitats provide shelter and a suitable environment for feeding and reproduction.
• Heath and Moorland: Although less common in these habitats, the beetle can still be found in some heath and moorland areas.

Conservation Status

The Devil’s Coach Horse Beetle is not considered a conservation concern, thanks to its widespread distribution and adaptability to different habitats. They are an essential part of local wildlife and contribute to maintaining a healthy ecosystem by controlling populations of pests, such as slugs and snails.

Behavior and Adaptations

Feeding Habits

Devil’s Coach Horse Beetles are predators with various prey items. They feed on:

• Insects
• Slugs
• Snails

They use their pincer-like jaws to catch and crush their prey.

Venom and Defense Mechanisms

When threatened, these beetles employ several defense mechanisms:

• Painful bite: Their strong jaws can deliver a sharp nip.
• Foul-smelling substance: They release a stench from their abdomen to deter predators.
• Curling up: They adopt a scorpion-like posture, raising their tail to intimidate potential threats.

These techniques are effective in warding off predators such as birds and mammals.

Predatory Nature

Devil’s Coach Horse Beetles are highly adaptive and skilled predators. Here are some of their known behaviors and hunting skills:

• Active during autumn: These beetles are most commonly found in gardens and soil during the fall months.
• Stealthy hunters: They move swiftly and silently to surprise their prey.
• Strong jaws: Their powerful jaws are designed to crush and hold onto their prey.

In conclusion, Devil’s Coach Horse Beetles are fascinating creatures with unique behaviors and adaptations suited for their predatory lifestyle.

Lifecycle and Reproduction

Egg to Larva

• Devil’s Coach Horse Beetles lay eggs
• Eggs hatch into larvae

Devil’s Coach Horse Beetles start their life cycle as eggs laid by female beetles. Once the eggs hatch, the larvae emerge. These can be observed with their elongated bodies, tiny eyes, and visible abdomens.

Pupation

• Short pupal stage
• Transformation from larva to adult

The larval stage then transitions to the pupal stage, which is comparatively short. During this phase, the larvae undergo significant changes in their body structures, transforming them into adult beetles.

Adulthood

Adult Devil’s Coach Horse Beetles have compact and sturdy bodies that grow up to an inch long. They possess six legs and are primarily nocturnal creatures, meaning they are most active at night.

Mating

• Involves both males and females
• Occurs during adulthood

The final stage of the lifecycle involves mating between adult male and female beetles. This process is essential for the continuation of the population and the beginning of the next generation.

Interaction with Humans and Environment

Importance in Gardens and Parks

The Devil’s Coach Horse Beetle plays a beneficial role in gardens and parks. Its presence indicates a healthy ecosystem since these beetles feed on other invertebrates, helping to maintain balance among various species.

• Benefits in gardens: They contribute to soil aeration, which promotes healthy plant growth.
• Benefits in parks: By controlling the population of invertebrates, they help maintain a balanced ecosystem.

Pest Control Role

Another advantage of having Devil’s Coach Horse Beetles around is their role in pest control. They are natural predators of various pests, including slugs and snails, which can destroy plants in gardens.

Pros:

• They help control pest populations, protecting plants from damage.
• No need to use chemical pesticides, which can harm other beneficial organisms and the environment.

Cons:

• Like many invertebrates, Devil’s Coach Horse Beetles can be sensitive to pesticides. If chemicals are used in the garden or park, these beetles may be affected as well.

Mythology and Folklore

The Devil’s Coach Horse Beetle has been associated with various mythologies and folklore, especially in the Middle Ages. Its appearance, resembling a small black scorpion, has led to superstitions and symbolism.

• Middle Ages: People in Europe believed the beetle was a curse or an omen of misfortune, due to its frightening appearance.
• Australasia: Some indigenous communities have associated the beetle with spiritual entities or ancestral beings.

In summary, the interaction of Devil’s Coach Horse Beetles with humans and the environment is primarily positive through their roles in pest control and maintaining ecosystems. While they have been associated with mythology and folklore, their ecological importance should be appreciated and preserved.

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 – Devil's Coach Horse

Slinky black 6-legged bug
Location:  Portland, Oregon
September 22, 2010 5:35 am
Oh, Bugman,
I just discovered this site and I fervently want to know ”What is this bug?” It appeared in my kitchen yesterday, and I’ve never seen one like it in my life.
I’m not normally too bug-phobic, but this bug is so unusually slinky for a beetle-type bug, it just creeps me out. I’m truly tempted to bug carnage, but no. I guess I will release it, at least 10 blocks away…
Anyway, it’s solid and kind of velvety black, 6 legs, 1.25 inches long, with antennae. It looks mostly like a beetle, but it’s arched between the head and thorax, and the abdomen has two parts: rigid where it joins the thorax and then at the end very flexible — even slinky. So slinky, it’s just creepy!
I would love to learn what it is, if you can help. It was hard to get a good photo; hope these give you an idea.
Signature:  Kelly

Kelly Self-Identifies Devil’s Coach Horse
Aha, Devils Coach Horse!
September 22, 2010 5:56 am
Daniel,
I just decided to click on each type of beetle, and found an exact match — interestingly from Troutdale, OR, from a month ago. I wonder if the DCHs just made it to Oregon, ’cause I have sure never seen one before.
I didn’t see the scorpion-like effect, but the name is apt. This bug has bad vibes. However, if it eats slugs and snails, I will not take it 10 blocks away — I will release it in my vegetable garden post haste!
Love, love, love your site!
Signature: Kelly

Dear Kelly,
We are happy to hear that you quickly self identified your Devil’s Coach Horse, Ocypus olens, using our archive, and we are also happy to hear that you have considered getting along with this introduced species provided it stays in your garden and not your home.  Since the Devil’s Coach Horse was introduced to North America around 1930, we are not certain of the extent of its range, but BugGuide’s database indicates it is established in Oregon and California.  BugGuide does report three members in the genus, which expands the range even more, but we are not certain how to tell the species apart as they look so similar.

Daniel,
I should have clarified that my Ocypus olens was actually 5-legged, and the posted image shows the 2-leg side.
A happy ending (but not for the slugs): I released the Devil’s Coach Horse into the garden this morning, and she/he immediately ran for cover under a leaf. As another reader reported, this bug does seem light-averse. As skeeved out as I was at first by it, after living with it (safely contained) for a couple days, I found that familiarity bred tolerance. Just before I released it, I showed it to a friend who was as revolted as I had been initially. But I felt… almost… fondness?
I will check out your book. BTW, thanks to you I will never again crush a house centipede.
Cheers,
Kelly

Letter 2 – Devil's Coach Horse

Bearish Beetle?
Location: Newark, California
June 1, 2011 9:30 pm
Hi bugman! I found this bug under a log in the backyard (I was looking for crickets to feed to my Scrub Jay friend and frequent backyard visitor).
The insect has a nasty disposition, raising its rear and menacing with its large mandibles.
So, my question to you, ”What is that bug?”
Signature: John in California

Dear John,
This marvelous Rove Beetle is commonly called a Devil’s Coach Horse.  It is a species that was introduced from Europe sometime in the 1930s and it has adapted to life in California.  It is commonly found in gardens where it feeds upon another introduced species, the garden snail, which is able to survive because of the frequent irrigation needed to sustain a European style garden in southern California.  When threatened, the Devil’s Coach Horse, Ocypus olens, rears up in the manner illustrated in your photograph, and our readers frequently describe it as acting like a scorpion.  It does not possess a stinger, but it does have scent glands at the tip of its abdomen and it will release a foul odor.  You can find other images in our archive or by searching BugGuide.

Daniel,
Thank you for the speedy reply. You’re amazing! I’m recommending your site to anybody else with a interest in the bug world. I eventually release the Rove Beetle back to the log pile. Thank you for the identification and interesting background on the critter.
John

Letter 3 – Devil's Coach Horse

Pincher bug family?
Location: Northern California
June 4, 2011 4:06 pm
My son discovered this bug while playing in the backyard today. It seems to be 2 to 3 times the size of a normal pincher bug and would raise its rear when prodded. What is this bug?
Signature: Backyardigan

Dear Backyardigan,
This is one of our favorite insects, a non-native Rove Beetle that has been introduced to California from Europe that is commonly called a Devil’s Coach Horse.  It is not dangerous.  They are one of the few insects that will feed on snails.  Your letter will post live to our site next week.

Letter 4 – Devil's Coach Horse

had a good look at your site…
…and searched under things mentioning scorpions but could find nothing like the bug shown in the attached pictures. This tiny little fellow had fallen into the pool and climbed up onto the skimmer paddle to dry. The tail is raised like a scorpion but that’s the only similarity. The tail also sat flat but it seemed to prefer having it raised like this most of the time. I scooped it out and let it wander away on the lawn.
Best wishes,
Ian

You are a kind man Ian.
You will be rewarded by having this species of Rove Beetle, originally a European immigrant, eat the snails and slugs in your yard. This beetle is commonly known as a Devil’s Coach Horse, Staphylinus olens, and though it appears threatening, it is harmless.

Letter 5 – Devil's Coach Horse

Help ID’ing a bug
Hi, can you help me identify the following very scary looking bug I found in my Seattle office? It raised its hind up like a scorpion to sting when it got scared (I’m speculating on its emotional state), and it appears to have a stinger, as well as some nice pincers? 6 legs and a couple antennas, I think.
Thanks!
Jason

Hi Jason,
Though an introduced species from Europe, this Rove Beetle, the Devil’s Coach Horse, is a gardener’s friend since it is one of the few predators that will eat snails and slugs. The defensive posture is a sham as the beetle has no stinger. It is harmless.

Letter 6 – Devil's Coach Horse

Black Bug w/attachment
Please find attached some pictures in a zip file of this black bug I can’t identify. It prefers shady areas and when threatened it either flips on its back and feigns death or it raises its tail up much like a scorpion. I’m not sure if its tail is barbed though. I’m in ireland and haven’t seen this type of bug around here before. Could it posibly be a more exotic species come in on imports of fruit or such? Thanks for your time, much obliged.
Conor

Hi Conor,
I have Devil’s Coach Horses, Staphylinus olens, in my Southern California garden. It is native to Europe, but was introduced to Southern California in 1931. They are great in the garden because they eat snails and slugs. Though they have a frightening defensive posture, they have no sting, but can emit a malodorous fluid leading to its scientific name which means stinking.

Letter 7 – Devil's Coach Horse

What’s this bug?
I was working on a car in Azusa, CA, and saw this bug coming towards me. I stopped and bent down to look at it, and the wind from my pants made it do what it’s doing in the picture. I’ll continue to have bad dreams about this bug until I find out what the heck it is. Please help.
Kevin

Hi Kevin,
Despite its aggressive posturing, the Devil’s Coach Horse is harmless. It is a European import and we love them in our garden where they prey upon snails and slugs.

Letter 8 – Devil's Coach Horse

What is this?
I had a question. Once in a while I see these weird black beetle looking bugs around my house and was wondering if you might know what they are. Here is a pic I took of one today.
Eric

Hi Eric,
We love the European Rove Beetle, diabolically known as the Devil’s Coach Horse, because they are one of the few predators that eat snails ande slugs in our Mt. Washington garden.

Letter 9 – Devil's Coach Horse

Devil’s Coach Horse?
Hi.
After browsing your site I think my bug looks like a Devil’s Coach Horse but I’m not sure. The bug was very soft to touch (yak). The photo was taken in Tuscany, Italy. A friend of mine who is quite into animals but not really into bugs says it’s a short winged bug. Do you know the latin name?
Mark.

Hi Mark,
This is a Devil’s Coach Horse, Staphylinus olens. The species was introduced to California around 1931 from Europe. We love them in our garden where they eat snails and slugs. Eric Eaton just gave us this update: “Oh, Staphylinus olens is now Ocypus olens, for the time being at least!”

Letter 10 – Devil's Coach Horse

Devils Coach Horse
Hi BugMan,
Fairly certain this is a Devil’s Coach Horse, although happy to be corrected. Spotted it scurrying along the side of the pavement outside our office near Glasgow, Scotland. It was definitely fierce and kept doing its scorpion pose and waving its jaws. I really struggled to get a photo from anywhere but the back because as I maneuvered round to get a photo from the front it kept turning to face its tail towards me! I read on the ‘net that they grow up to 28mm – however I am convinced this one was more (I am ashamed to admit I have come to this conclusion from using the pattern of stones in the photo to identify where it was taken and then measuring various distances) any info on maximum length? Great site! Cheers,
Robbie Gorman

Hi Robbie,
This is indeed a Devil’s Coach Horse, a type of Rove Beetle. This European native was introduced to Southern California in the 1930s and it has adapted quite nicely. We frequently find them in our garden where they eat snails. Hogue lists body length at 33mm.

Letter 11 – Devil's Coach Horse

IS IT EMBIOPTERA ?
Hello,
Herewith I’m sending you something like Embioptera, but the first 2 legs are not similar as it is shown in your picture. The creature was found on the attitude of 900 m. Yeah, I’m writing you from EU – Slovenia. Thanks in advance for your kind assistance.
Janez Kamin
Nova Gorica
Slovenia

Hi Janez,
Believe it or not, this is a beetle. The Devil’s Coach Horse is a type of Rove Beetle. These native Europeans are now well established in Southern California.

Letter 12 – Devil's Coach Horse

Interesting find
Hi,
I found this in my front garden ( Hampshire ,England ). I don’t think it’s a scorpion, but it looks quite like one. It was about an inch long with its tail flat. Would appreciate finding out what it is, and could it hurt my 9 month old child? Thanks a lot,
Matt Stephenson

Hi Matt,
This large, black soft-bodied Rove Beetle is commonly called the Devil’s Coach Horse. Its scientific name, Ocypus olens, formerly Staphylinus olens, refers to a foul odor it discharges when disturbed. Your image shows the scent glands portruding from the anus when the beetle assumes its threat position. This beetle was introduced to North America sometime in the 1930s. It is quite common in our Mt. Washington, Los Angeles garden where it feasts on an introduced pest, the Garden Snail. Though it can bite, it is nothing more than a nip, so the Devil’s Coach Horse will not harm your child.

Letter 13 – Devil's Coach Horse

All black hard shelled with large mandables and stingers on tail.
We have been finding these bugs at my work for the last few weeks. I’ve lived here in Western Washington my entire life and never seen anything like this. It is a very aggresive bug, it has large mandables and its back end will curl up like a scorpion when aggrivated and it looks like two stingers potruding from its rear. It eats crickets with ease and also eats its own kind with out hesitation, but some good battles. Please let me know what it is. I don’t think its native, we receive alot of shipments from around the world.
Badest bug in the west
Northwest

Hi Badest,
Your beetle is known as a Devil’s Coach Horse, and it is an introduced species of Rove Beetle.  Sometime in the 1930s, the species made its first appearance, expanding it original range from Europe.  I cherish the Devil’s Coach Horse in my garden since they are one of the few predators that will eat snails and slugs.  Despite the threat posture, there is no stinger and the Devil’s Coach Horse is not poisonous.  The mandibles are strong, but will do little more than deliver a slight nip to a human.  The Devil’s Coach Horse goes by the scientific name Ocypus olens.

Letter 14 – Devil's Coach Horse

What’s That Bug?
December 3, 2009
i foudt it on a balcony in rotterdam
it was in summer
sorry for the english 😀
posthumen
netherland

Dear posthumen,
This lovely creature is a Rove Beetle known as a Devil’s Coach Horse.  The threat posture is all show as the Devil’s Coach Horse has no stinger, however it does possess scent glands and it can release a foul odor.  This European species has been introduced to the U.S. and we love them in our garden since they eat snails.

Letter 15 – Devil's Coach Horse

Oddly large and long insect
Location:  Troutdale, Oregon.
August 26, 2010 3:02 am
I was outside picking up after my children this evening. It was dark, and I noticed this oddly large and long insect, it seemed to be rather aggresive when I scooped him/her up to take a picture. It was crawling over a graveled area next to my lawn. (there is quite alot of grass and weeds growing through the gravel) I spent nearly two hours online trying to identify the critter with no success. I would be very interested to know what type of insect this is, as I have never before scene one. It was approximately 1 inch long, with large mandibles, and the tail section curved upwards when threatened, like you would see a scorpions tail do, along with the mandibles opening.
Thank you so much for your assistance.
Jason
Troutdale, Oregon

Dear Jason,
Though it looks more like a larva, this Devil’s Coach Horse, Ocypus olens, a species of Rove Beetle, is actually a mature adult.  It was introduced from Europe in the mid twentieth century.  These are predators and we have read that they will eat snails and slugs.

Letter 16 – Devil's Coach Horse

My Devil’s Coach Horse thanks you!
Location: San Francisco, California
November 6, 2010 12:38 am
Dear bugman –
What’s That Bug is my first stop when I find myself exclaiming, ”what the hell is that?” at the squirming black mass my cat has cornered ’neath the table.
Though I had planned to send a somewhat-panicked missive asking you to identify said mass, I was able to easily identify him myself as a Devil’s Coach Horse (whom I also call Satan’s Change Purse).
But I thought you might like an additional photo of this guy for your site. Enjoy! My cat sure did. Just kidding, I put him back outside with a pat on the head and a nickel for his trouble.
Signature: Somewhat relieved

Dear Somewhat relieved,
The European Rove Beetle commonly called a Devil’s Coach Horse is not a native species in North America, but it has become well established on the West Coast.  This is a highly active beetle in both the adult and larval stages, and the Devil’s Coach Horse does not go through a dramatic metamorphosis with the adults retaining many of the characteristics of the larva, though it is uncertain if it is considered a larviform imago.

Letter 17 – Devil's Coach Horse

Small bug with scorpian curled tail
Location: Spain
November 30, 2011 9:51 am
Are you able to identify this bug that crawled out of my slipper…. it looks like it could sting and small wings on its tail???
Signature: Hazel

Hello Hazel,
This frightening but harmless creature is a species of Rove Beetle that is native to Europe, but which has naturalized in many parts of North America where it is called a Devil’s Coach Horse.

That is ever so kind of you to reply and let me know, I shall let the poor thing free now. Thank you again for your quick response.

Letter 18 – Devil's Coach Horse

Subject: gaahhh. a strange bug
Location: Portland Oregon
September 25, 2012 11:10 pm
hi there bugman. we found this bug on our concrete patio behind our house.
It’s about 1 1/2” long and quite peculiar to us.
We found him (er.. her?!) just after dark in Portland Oregon on Sept 24th.
Joey, as my daughter calls him, hasn’t stung anyone, but seems to have a nice set on his backside.
He’s now residing comfortably, perhaps, under a glass jar.
We’d love to hear your thoughts!
Thanks
~tom and Lucy
Signature: Bugman Extroadinaire!

Dear tom and Lucy,
Joey is a Devil’s Coach Horse, a species of Rove Beetle that is native to Europe, but established in North America prior to 1930.  It is a harmless beetle that uses a defensive threat posture of curling its abdomen over its head.

Letter 19 – Devil’s Coach Horse

Subject: Bug?
Location: west Lothian, Scotland
August 9, 2016 10:31 am
Hi I was wondering if you could tell me what this insect is I seen in my garden, never seen 1 before till this. Thanks
Signature: L a ramsay

Dear L a ramsay,
This is a Rove Beetle commonly called a Devil’s Coach Horse.  When disturbed, it will curl up its abdomen like a scorpion and release a foul smell from scent glands.  The Devil’s Coach Horse has been introduced into Southern California and it is now well established in western North America where it feeds on introduced snails and slugs.

Letter 20 – Devil’s Coach Horse

Subject:  Gnarly bug
Geographic location of the bug:  Kent, Great Britain
Date: 09/30/2017
Time: 05:37 PM EDT
Hi,
Found this bug in my bathroom a few days ago, is roughly 2-2.5inches long. Found a second, smaller one in kids bedroom this evening.
Brick built house, roughly 7years old. Just coming into autumn here in UK and weather has been approx. 15-20C the past week.
Hope that helps
How you want your letter signed:  Many thanks  Ken

Dear Ken,
This is a predatory Rove Beetle that is commonly called a Devil’s Coach Horse.  According to Nature Spot:  “This beetle is found in damp conditions in most natural environments including: woodland, hedgerows, parks and gardens, where it relies on decaying natural matter.”  According to the Royal Horticultural Society:  “Two beetle families are largely ground dwelling and predatory and should be considered  gardener’s friends: ground beetles (Carabidae) and rove beetles (Staphylindae). …  The matt black devil’s coach horse (Ocypus olens) is Britain’s largest rove beetle and is often found in gardens under logs or pots.”  Thank you for providing images of both the threat posture and the more relaxed position.  When threatened, the Devil’s Coach Horse will curve its abdomen over its head like a scorpion, but instead of stinging, it releases a foul odor.

Letter 21 – Devil’s Coach Horse

Subject:  What is this creature?
Geographic location of the bug:  Richmond, BC Canada river front
Date: 09/11/2019
Time: 06:34 PM EDT
Your letter to the bugman:  I found this little guy scurrying on the basement floor of our house. For a moment I thought it was a caterpillar and was going to stomp on it, but I realized he was not going to become a moth and took some pics. I’m pretty sure this is some sort of beetle but I’ve never seen one like this before! And FYI once I took these pics I let him go outside. I am of the same mind with respect to most bugs 🙂
How you want your letter signed:  Dan

Dear Dan,
This interesting Rove Beetle is commonly called a Devil’s Coach Horse.