Where Do Blister Beetles Live? Can I Find Them Near My Home Too?

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Touching blister beetles can give you a nasty blister, so it’s important to stay away from them. But where do blister beetles live? Let’s find out in the article below.

Blister beetles are toxic field and garden pests that harm humans and animals.

They secrete a toxin called cantharidin which can cause skin irritation and blistering in humans and gastrointestinal issues, poisoning, and even death in animals.

They’re found all over the world, including in many places in the US.

In the following article, I will try to give you a comprehensive list of where these notorious pests are found.

Where Do Blister Beetles Live
Nuttall’s Blister Beetle

Where Do Blister Beetles Live?

The eastern and southern states in the United States see higher numbers of blister beetles. States like Oklahoma, Florida, California, North Carolina, Wisconsin, and Minnesota are home to many species of blister beetles.

The striped blister beetle and the black blister beetle are quite common here.

Apart from the United States, other countries such as the West Indies and South and Central America also have large populations of blister beetles.

What Is Their Habitat?

The most common place to find blister beetles is in alfalfa hay. This is because adult blister beetles often feed on the alfalfa blossoms.

Secondly, grasshoppers are the main source of food for blister beetles. Hence they will be found where grasshoppers are.

Blister beetle larvae, on the other hand, feed on nesting bee larvae and eggs of grasshoppers.

Hence, they are often found on the ground in habitats where their food sources are in abundance.

You can also find adult beetles on garden vegetables such as tomatoes, potatoes, and lima beans. You can also spot them on sunflowers, dandelions, and black-eyed Susan.

Master Blister Beetle

What Is a Blister Beetle’s Life Cycle?

Blister beetles usually have one generation per year. They are said to be the most active between June to September.

However, this may vary from species to species.

You may first spot blister beetles after the first alfalfa harvest, which is done somewhere around the latter half of April or during early May.

After mating, female beetles lay eggs directly in the soil during summer.

The eggs hatch during fall, and the instar blister beetle larvae emerge from the soil. They then look for clusters of grasshopper eggs and bee eggs to feed upon.

Grasshoppers lay their eggs around the same time the blister beetle larvae emerge from the soil, making them a convenient food source.

Blister beetle larvae can feed through several clusters of grasshopper eggs at a time.

Post-feeding, the larvae then transition into pseudopupae and overwinter before emerging as mature adults during late spring or early summer.

Adult blister beetles are mostly attracted to the flower clusters of alfalfa but can also feed on their leaves in the absence of flowers.

Blister Beetle

Apart from this, they also feed on peanuts, pigweeds, and soybean plants, among others.

While adult blister beetles are often not considered as plant pests that are serious enough for intervention, species like the striped blister beetle tend to gather in large swarms in alfalfa hay.

This can be concerning because a large swarm means a higher concentration of cantharidin. This could lead to blister beetle poisoning to the harvest as well as to the livestock, especially horses.

For this reason, horse owners should check the hay properly before giving it to their animals.

Cantharidin poisoning can be fatal to horses. It causes inflammation and poisoning of the gastrointestinal tract and can lead to death if ingested in large amounts.

Thankfully, it normally does not require medical attention in humans – the results are painful but temporary.

For blister beetle control, you can use either organic or chemical treatments. Organic works better in protecting the soil and other important insects like bees in your garden.

blister beetle
Blister Beetle

How Long Do Blister Beetles Last?

Blister beetles (also called oil beetles) have one generation each year, and adult beetles survive for over three months. They tend to thrive in warm climates where their population can expand quickly.

If you find a blister beetle infestation in your garden or field, it’s best to immediately use either a chemical or organic treatment to rid the infestation.

Blister beetles secrete a toxin called cantharidin which can cause irritation and blisters on human skin. If ingested, it can irritate the digestive tract.

If you have come into direct contact with blister beetle toxin, you may notice blistering within 24-48 hours. While it’s not life-threatening, it is painful, and symptoms can carry on for around a week.

Frequently Asked Questions

Do blister beetles bite humans?

The short answer to this question is “no”. Blister beetles do not bite humans.
However, they can cause skin irritation if they come into direct contact with human skin. This is because they secrete a chemical called cantharidin, which is a vesicant (a substance that produces blisters).
If a blister beetle comes into contact with your skin, you may develop a skin reaction called cantharidin toxicity.
This condition is characterized by developing blisters or vesicles on the skin. In severe cases, cantharidin toxicity can lead to death.
Fortunately, cantharidin toxicity is rare and usually only occurs if there is direct, prolonged contact with the blister beetle. So while blister beetles may be a nuisance, they pose little threat to humans.

Do blister beetles live in the ground?

Ground-dwelling blister beetles are commonly found in areas where there are high populations of termites or ants.
These beetles feed on insects, which can be hazardous to crops and people.
While most species of blister beetle occupy plants, some species prefer dwelling underground.

What attracts blister beetles?

Blister beetles are drawn to certain plants due to their chemical makeup. Solanaceae-family plants, like potatoes, tomatoes, and eggplant, are particularly attractive to blister beetles.
Other plant families that tend to draw in these bugs include alfalfa, clover, and cotton.
The presence of compounds that attract blister beetles is typically found in the leaves, stems, or flowers of the target plants.

Can blister beetle harm you?

Yes. Blister beetles contain a toxic substance called cantharidin, which, if ingested, can cause skin blisters and irritation as well as gastrointestinal upset.
In more serious cases, ingestion of cantharidin may lead to kidney damage, coma, or even death.
Despite its toxic nature in humans, it is used in some medical treatments such as wart removal and has been studied for its potential cancer-fighting effects.
It’s best to avoid contact with these beetles altogether; however, if you do come into contact with one, immediately wash the area of contact and get medical attention if needed.

Wrap Up

Blister beetles are commonly found in places where there’s an abundance of grasshoppers and their eggs and bee eggs.

Alfalfa fields are also home ground for these beetles as they feed on alfalfa flowers.

You may also find them on other garden vegetable plants like tomatoes, potatoes, and soybean.

Blister beetles are spread across North America’s eastern and southern states and other countries like the West Indies, South America, and Central America.

Thank you for reading! I hope I covered all you needed to know about where to find and be mindful of these bugs.

Reader Emails

Blister beetles are quite dangerous, especially for livestock and horses.

That’s why we have often got concerned emails from our readers asking us to identify bugs (that are often not even blister beetles).

Go through some of these letters below, which are sometimes serious and at other occasions, will give you a chuckle.

Letter 1 – Blister Beetle in Spain


Bug in Spain
Just wondered if you could help identify this bug that appears quite extensively in the garden of our house in Andalucia, Spain. They are about 6 cm long and “seem” perfectly harmless, but it would just be interesting to know more about them. Any help appreciated. Many thanks
Andrew Mair
El Berrueco, Cadiz, Spain

Hi Andrew,
This is a Blister Beetle, probably in the genus Megetra. Though you call them harmless, Blister Beetles exude a fluid that contains Cantharidin, and if handled, it can cause blistering of the skin.

Update:  April 4, 2010
We have just identified this species as the Red Striped Oil Beetle, Berberomeloe majalis, based on information on the Wildside Holidays website.

Letter 2 – Blister Beetle from Portugal


Black insect with red stripes
Hi, Just found the name of this bug: Meloe majalis. You can find some detailed information (if you’re interested) here: http://www.faculty.ucr.edu/~legneref/taxonomy/meloidae.htm

(04/28/2008) Hi again,
I just found on the web some pictures of similar bugs. It seems to be a Megetra. However I did not find one looking exactly like this and could not find any reference to european Megetras.

(04/27/2008) Black insect with red stripes
I live in Portugal and found this “little” guy wandering around. I had never seen such an insect. Can you help me identify it? It is about 5cm long, runs quite fast and its body is flexible. Thanks.

Ed. Note: As with many of our submissions, we had an offline dialog with Michelle regarding her Blister Beetle. Eventually she provided a more exact identification and we are posting her submission.

Letter 3 – Blister Beetle from Spain


Many thanks for your help with the identifying of our seed bugs but once more I am seeking your help. As ‘trainee crop growers, we live in Southern Spain and found this wandering along the ground nibbling at most things green. Can you identify it for us please. Best regards

Just want to say that I am sorry and should have checked ALL of your site before asking the question.
I now know that it is a spanish blister beetle, but does it do any harm to plants or humans?

Hi Maggie,
We are happy to hear you identified your Spanish Blister Beetle using our site without our assistance, since we are starting to get more and more letters again as summer approaches. Adult Blister Beetles eat plants, and can get very numerous at times. They can do significant damage. Larval Blister Beetles often feed on Grasshopper Eggs, which is beneficial to farmers. We feel the Blister Beetles are important contributors to the balance of nature. Many Blister Beetles exude an irritating chemical compound that will cause blisters in humans. We have never taken the time to correctly identify this Spanish species, but it looks nearly identical to the genus Megetra found in North America.

Update:  April 4, 2010
We have just identified this species as the Red Striped Oil Beetle, Berberomeloe majalis, based on information on the Wildside Holidays website.

Letter 4 – Blister Beetle from Germany


Large, Metallic Blue Ant-Like Insect in Germany
September 1, 2009
I found this creature a few months back and haven’t been able to identify it.
I was walking in a hilly wooded area (deciduous) in May, 2009 on the warmer, south side of the hill. It had been a bit rainy and already warm for a few weeks after a very hard frost toward the end of winter. At this time, apple trees and wild garlic were blooming…
The animal in question was ~4-4.5 cm in length and fairly quick-moving.
I watched it for a few minutes until it was clear of the footpath/road, took a few pictures (including the horribly blurry one for scale) and left it be.
I understand that you get quite a few requests for IDs, but if you get a chance, I’d really like to know what this was. Thanks!
Kreutzwertheim, Germany (Spessart Forest, Northwest Bavaria/Northeast Baden-Württemberg)

Blister Beetle from Germany
Blister Beetle from Germany

Dear Cori,
This is some species of Blister Beetle.  It greatly resembles the North American Oil Beetles in the genus Meloe which can be viewed on BugGuide.

Dear Daniel,
Thank you for such a quick response! – I would never have guessed to call it a beetle. I believe I will ask one of the local beekeepers and see if it is one of the varieties that uses bees for reproduction. – Either way, they might know more about the local insect populations. I don’t know why I didn’t think of it before.
Thank you again,

Hi again Cori
Should you happen to find out any additional information on this fascinating Blister Beetle, please provide us with an update.

Will do!
I’ve been in the research field (geology) long enough to know that you mean that! Yay for other people doing the legwork … but don’t forget to double-check it! … 🙂
Best wishes,

I know that in Germany there are at least 14 members of the genus Meloe. But this should be Meloe violaceus at least if the colour of the beetle from the picture is blue not black with blue glister/gloss (don’t know which one of these words is proper). Little verified link about the species appearance.

Letter 5 – Blister Beetle from Croatia


Black and orange beetle
September 16, 2009
Found on the top of high grass in the summer on Croatia’s Mediterranean coast, these beautiful beetles seem to not be bothered by the hot midday sun. They can and will fly away if given the opportunity when captured (not the stuff seen in the first picture, those are remains of potato chips). They cannot bite, and often leave traces of a yellow substance similar to ear wax when captured. They are usually about 1-2 centimeters long.
Croatia, Mediterranean coast

Blister Beetle we believe
Blister Beetle

We believe this is a Blister Beetle in the family Meloidae.  We will try to get a second opinion.

Eric Eaton Confirms Identification
Right again!  See how good you have gotten?:-)  Have a great day….

Letter 6 – Blister Beetles from Bolivia


Bolivian Blister Beetle, Epicauta pardalis?
February 13, 2010
These blister beetles are destroying hot pepper harvests here by cutting off the immature peppers and flowers. The closest thing I can come up with is Epicauta pardalis, the spotted blister beetle but I am not sure without a good guide or key. I would like to identify it so I can help the people I work with repel it. I’m thinking of maybe a Neem spray. Know of any good way to repel blister beetles? We are in late summer/rainy season here.
San Jose, Bolivia

Blister Beetles from Bolivia

Hi Jay,
We doubt that this is Epicauta pardalis, a species represented on BugGuide by individuals from Arizona, but it does appear to be the genus Epicauta.  We believe it resembles Epicauta maculata more, which you can verify on BugGuide, but we are uncertain if Epicauta maculata is found in South America.  Alas, we do not give extermination advice.  If it is any comfort, Blister Beetles tend to appear in great numbers for a very short period of time, so your problem may alleviate itself naturally in a short time.

Thanks for the help, Epicauta maculata seems more acurate.  I prefer to repel pests or find natural solutions rather than extermination. I’ll probably experiment with a Neem leaf “tea” to repel them, if they haven’t moved on already by now. Thanks for the help!

Letter 7 – Blister Beetle from China: Possibly Lytta species


Red headed Chinese beetle for Identification
February 15, 2010
Dear Bugman,
I would be very grateful if you could help identify this beetle to any taxanomic level. I saw it in Sichuan province last July on a mountain path at about 600-900m. To my inexperienced eye it is very unusual but my guess is it’s some kind of rove beetle.
Sanmeishui, Sichuan

Blister Beetle

Hi Ed,
Though Rove Beetle was a good guess, this is actually a Blister Beetle in the family Meloidae.  It resembles many North American species in the genus Lytta, which you can compare on BugGuide, so that genus is our best guess at the moment.

Hi Daniel, thank you for your ID. Yes I see now it is a blister beetle and that
they have quite a characteriustic shape. Lytta looks like the correct genus, I
see that many species have different patterns of red on their head and thorax
with a black abdomen. Must be closely related to these N American spp.
Best Wishes

Letter 8 – Blister Beetle from Spain


ID Please
April 4, 2010
Hi, we discovered this creature during a walk with our dog. It isn´t a fast creature but does move reasonably well. We saw two, one was injured and looked to be bleeding, a red liquid was oozing from it. The second was unharmed and moving well.
Many thanks
La Manga, Southern Spain

Blister Beetle

This is a Blister Beetle in the family Meloidae and the red liquid you observed was the hemolymph that contains a substance cantharidin that will cause irritation to skin and possibly blistering.  This may be Berberomeloe insignis which we located on the Wildside Holidays website.

Hi Daniel,
Thank you so much for Identifying the creature for me and taking the trouble to e-mail and let me know.  It´s very much appreciated.
Andy Baxter

Letter 9 – Blister Beetle from India


Flower eater
Location: Punjab, India
July 6, 2011 1:08 am
Hello! I found these giants busily eating my okra flowers. Any idea what they are?
Signature: Jerah

Blister Beetle

Hi Jerah,
We are really running late for work, and we need to meet with architects this morning, but we had to find time to post your exciting photos of Blister Beetles in the family Meloidae.  Handle with caution.  We also found a species name,
Mylabris pustulata, on the Science Photo Library website.

Blister Beetle

Letter 10 – Blister Beetle from Turkey


Red one with black spots
Location: Turkey, İzmir
August 20, 2011 2:43 am
I want to know what is these. In which family?
Thank you very much
Signature: Sertaç TURHAN

Blister Beetle

Dear Sertaç TURHAN,
This is a Blister Beetle in the family Meloidae, and we posted a similar looking Blister Beetle from Croatia several years ago that we never identified.  We found an article published on the internet, Blister Beetles (Coleoptera: Meloidae) in Nahavand County (Hamedan Province, Iran) and Their Ecological Relationship to Other Coleopteran Families by MR Nikbakhtzadeh, S Tirgari that has photos of two very similar looking beetles,
Mylabris variabilis and Mylabris impressa.  The Beetles (Coleoptera) and Coleopterologists website has a photo from this genus attributed to A.N. Posedko that is also very similar.  We believe your beetle is also in the genus Mylabris.  Blister Beetles should be handled with extreme caution, or better yet, not handled at all, as they can excrete a substance that causes blisters on skin.

Letter 11 – Blister Beetles from Namibia


Location: Namibia, Southern Africa
November 20, 2011 2:39 pm
Can you please identify these beetles. Images 1 & 2 were taken around 9a.m. on 13th April 2010. in the gardens of Nunda Lodge near Divundu, in the Caprivi Strip, Namibia. The beetles were very abundant and we saw them again when we returned in April 2011.
Signature: Roger Pinkney

Unknown Blister Beetles from Namibia

Hi Roger,
These colorful creatures are Blister Beetles in the family Meloidae.  The larvae often feed on Grasshopper Eggs or they parasitize the nests of Solitary Bees.  Adults feed on vegetation.  They have a complicated life cycle.  Blister Beetles get their common name because they exude a substance called cantharidin that can cause blistering of skin, so they should be handled with care.  We need to leave to get to Whole Foods to buy some cheese for Thanksgiving dinner, but we will try to find a species identification upon our return.

Blister Beetles

While your individuals look very similar to this unidentified species from Namibia the distinctive red markings evident in your photo are absent.

Dear Daniel, Many thanks for another swift identification. Glad we didn’t touch these beetles. Enjoy your Thanksgiving dinner. Kind regards, Roger.

Hi Daniel and Roger:
Your Blister Beetles probably belong to the genus Mylabris (Meloidae: Meloinae). It’s a very large genus (apparently over 200 species) so as usual I can’t be certain, but it looks very much like M. tricolor. The species probably occurs throughout Southern Africa as I also found references to it from Angola and Botswana, as well as images from Zambia, Mozambique and South Africa. None of these images look exactly the same as those in the submitted photos but all are very similar. Variability in appearance is quite common within insect species, particularly if the species has a wide distribution, so that may account for the small differences. Unfortunately, I couldn’t find any additional information about the species. Regards.  Karl


Letter 12 – Blister Beetle from Ethiopia: Lydoceras flavosellata


Subject: Ethiopian Beetle sp.
Location: Arero area in Southern Ethiopia
March 10, 2013 5:48 pm
This was a quite big beetle maybe 4 cm. Could it be some kind of oil beetle?
The photo was taken november 10, 2006.
Signature: Kristian

Blister Beetle
Blister Beetle:  Lydoceras flavosellata

Hi Kristian,
Thank you for all your submissions, and thank you for keeping each species as a separate submission.  We will try to post as many of your images as possible.  This is some species of Blister Beetle in the family Meloidae, but we haven’t had any luck matching it to any online images at this time.  Oil Beetles are included in the family Meloidae.  Your individual looks somewhat similar to this unidentified African Blister Beetle we found online and the coloration is similar to this Tanzanian Blister Beetle posted to dijitalimaj.
  Perhaps one of our readers will have better luck determining an actual species.  For now, the best we can provide is the family.

Hi Daniel,
I think you doing a fantastic job. It is really hard for a guy like me to know where to look on the internet, to get the correct id of these creatures. And I don’t have any books either. I’m a keen birdwatcher, and know how “look-a-like” two species can be. Therefore I have great respect when it comes to id insects. There are a few more insect species than bird species, so I imagining  that there are alot more insects that are “look-a-likes”.
But I think it is really fun to know what species I’ve seen, so therefore I’m grateful for all help I can get from you. Hope there will be some of the bugs that can be id to species-level. And I have some more insects that I have problems with so I will keep them coming.
Great thanks!!

Update:  October 22, 2013
We received a comment from Standa today that identified this as
Lydoceras flavosellata and provided this link.

Letter 13 – Iron Cross Blister Beetles from Baja California, Mexico


Subject: What is this insect-Baja California
Location: 8 miles north of town of San Felipe, Baja California, Mexico
March 27, 2013 3:25 pm
We just visited our property in San Felipe, Baja California, Mexico and their were swarms of these bugs all over our property. They didn’t seem harmful. They were snacking on any new green foliage in the desert. I’ve been going down there for several years and have never seen these. They are quite large, maybe an inch and one-half long. Golden wings. Their were some on their own, but mostly on the ground in clusters. I suppose that had to do with the vegetation they were eating. I moved some around and they didn’t try to sting or bite.
Signature: Baja Barb

Iron Cross Blister Beetles
Iron Cross Blister Beetles

Dear Baja Barb,
These are Iron Cross Blister Beetles in the genus
Tegrodera.  There are several species in the genus and we have difficulty distinguishing one from the other.  According to BugGuide:  “species closely related, separable by minor but consistent differences of adult anatomy.”  BugGuide also notes that:  “each sp. associated with different plant communities” and “Eriastrum is an important food source for all adults.”  All Blister Beetles should be handled with care as they are able to secrete a compound known as cantharidin that can cause skin to blister.

Iron Cross Blister Beetle
Iron Cross Blister Beetle

Letter 14 – Blister Beetle from Honduras: Cissites species


Subject: Large Orange and Black Honduras Bug
Location: Comayagua, Honduras
September 20, 2013 3:43 pm
I’ve got a weird one for you.
It’s what looks like a 3 inch long orange and black ant. And it has terrifyingly huge pincers on it.
I’m in the Air Force, right now stationed in Honduras. I found this creature on a tree near where I’m living. I have no idea what it is. If you have an idea, please let me know.
Signature: Ryan Cwynar

Blister Beetle:  Cissites species
Blister Beetle: Cissites species

Hi Ryan,
We immediately recognized this impressive insect as a Blister Beetle in the genus
Cissites, most likely Cissites auriculata, which ranges from “w. & so. TX / Mex. to Costa Rica / W. Indies” according to BugGuide.  The larvae are parasitic on Carpenter Bees and BugGuide also notes:  “found in the US only recently” which might be related to global warming.

Blister Beetle and Ryan's Thumb
Blister Beetle and Ryan’s Thumb

Oh, cool.
Just did some searching. They EAT bees, and secrete a blister agent.
That’s a scary bug. There’s a photo on your sit of someone handling
one. So they only secrete the stuff if they’re startled?

Hi again Ryan,
We cannot say for certain what the individual characteristics of the Big Eared Blister Beetle, as your species is sometimes commonly called, but we can direct you to University of Florida Institute of Food and Agricultural Sciences (IFAS) website where it states:”The family Meloidae, the blister beetles, contains about 2500 species, divided among 120 genera and four subfamilies (Bologna and Pinto 2001). Florida has 26 species, only a small fraction of the total number in the U.S., but nearly three times that in the West Indies (Selander and Bouseman 1960). Adult beetles are phytophagous, feeding especially on plants in the families Amaranthaceae, Compositae, Leguminosae, and Solanaceae. Most adults eat only floral parts, but some, particularly those of Epicauta spp., eat leaves as well.”  Regarding the secretion of Cantharadin, the blistering compound, the site provides this information generally on the family:  “Blister beetles receive their common name from the ability of their hemolymph to produce blistering on contact with human skin. Hemolymph is often exuded copiously by reflexive bleeding when an adult beetle is pressed or rubbed. Blisters commonly occur on the neck and arms, as the result of exposure to adult beetles attracted to outdoor lights at night. General handling of adults seldom results in blistering unless the hemolymph contacts the relatively thin skin between the fingers. Unless extensive, medical treatment beyond first aid for blistering on humans is probably not necessary.”


Letter 15 – Blister Beetle from Malaysia


Subject: Family Meloidae
Location: Kuching, Malaysia
October 23, 2013 7:22 pm
Hello Bugman,
I found this beetle a few years ago (2009?) before I was very interested in entomology. At the time I just thought it looked cool and took a picture. I was on a mission trip in Kuching, Malaysia. Now that I am studying entomology in college I have been more motivated to identify this beetle. I’m thinking that it is in the family Meloidae and the genus Horia. What do you think?
(I am resending this email because I am afraid the last one I sent did not have the picture attached. Sorry.)
Signature: Shiloh

Blister Beetle:  Horia species
Blister Beetle: Horia species

Hi Shiloh,
Our first impression was that this must be a Leaf Beetle in the family Chrysomelidae, but we looked up your suggestion.  The legs on your beetle are quite distinctive, but unfortunately, the photo is not ideal for revealing that feature.  We found a photo of a preserved specimen of
Horia roepkei on Meloidae.com, but we cannot say for certain it is the same species.  There are some wonderful photos on Wikipedia (not our first choice for citing) and they look remarkably like your image.  If we are trusting Wikipedia, then we believe you are correct.  We still wish you had a photo that showed the interesting features of this beetle a little better.  The World of Insects also has a photo that looks similar.

Letter 16 – Blister Beetle from Sudan


Subject: Poison Insect
Location: Nertiti, Darfur, Sudan
June 19, 2014 3:16 am
I’m Zumairi from Malaysia. No i’m working with UNAMID in Darfur, Sudan. In my Team Site in Nertiti, there is a bug that call by local as Fesseyah (it’s in arabic actually). According to the local’s, this bug is very dangerous and some of the local says it’s more dangerous than hornet! The colour of this bugs is dark green in the top while it’s abdomen and leg are black. It’ length is about 1 inch.
From local villager, i made to understand that this bug will appear themselves in within and after raining season. But sometimes i find it in whatever season. For your information, geographically, Nertiti is half desert which when the raining season, it will be green everywhere.
I need to know better about this bugs, because i never seen it before in Malaysia. And because, the local’s claim that this this bugs are very poison which can be fatal to human!
Signature: Zumairi

Blister Beetle
Blister Beetle

Dear Zumairi,
While we have not been able to identify your beetle to the species level, we can tell you that this is a Blister Beetle in the family Meloidae.  While we believe what you have heard is likely an exaggeration, it is well known that Blister Beetles are capable of secreting a compound known as cantharidin that can cause blistering in human skin.  The legendary aphrodisiac Spanish Fly is made by crushing the bodies of one species of Blister Beetle,
Lytta vesicatoria, and you can get additional information on Encyclopaedia Britannica online.  

Letter 17 – Blister Beetles from Morocco


Subject: Red and black striped beetle, High Atlas, Morocco
Location: High Atlas region, Morocco
June 11, 2015 2:33 am
I’m a fan of your website, and I appreciate how you help people understand their insect friends.
I went hiking in the high Atlas region between Marrakech and Ouarzazat in Morocco and saw (among many wonderful bugs) these red and black striped beetles. They were hanging out at the tops of a specific type of plant, which I assumed they were doing hoping for a chance of mating(?) I haven’t been able to identify them myself. Unfortunately, the picture isn’t very clear (it was windy and rainy).
Signature: Thanks, Leanna

Blister Beetles
Blister Beetles

Dear Leanna,
Thanks for the compliment.  We have been on holiday, hence the delay in our response.  Though your image is extremely blurry, we thought these resembled Blister Beetles, and we found this image on FlickR of a similarly colored and marked Blister Beetle from Morocco identified as being in the genus
Mylabris.  A similarly colored individual from India, also on FlickR, is identified as Mylabris pustulata.  The posting provides this information:  “Blister beetles are beetles (Coleoptera) of the family Meloidae, so called for their defensive secretion of a blistering agent, cantharidin, a chemical that causes blistering on human skin. The black and red stripes on the beetle’s body warn predators that it is poisonous.”

Letter 18 – Blister Beetle from Kenya: Mylabris oculata


Subject: Beetle pictured near Amboseli, Kenya
Location: Amboseli, Kenya
July 13, 2016 7:32 am
Hi there,
I was recently in Kenya and captured a few pictures of an interesting bug but none of the people there knew the name of it, nor do I know what plant it was eating (a rather lovely purple flower)
It was captured in July 2016, so Kenyan winter.
Can you please help identify it for my picture collection.
Signature: Tane Piper

Blister Beetle: Mylabris oculata
Blister Beetle: Mylabris oculata

Dear Tane,
This is one beautiful Blister Beetle in the family Meloidae and the colors on your image, the bold black and white beetle, the orange antennae and the ultraviolet purple blossom are stunning.  We quickly identified a similar looking Blister Beetle on the Kenya Natural History Guide that is identified as being in the genus
Mylabris.  The site states:  “Many blister beetles are so toxic to mammals that ingestion of a few may be enough to kill a horse. It happens occasionally when the beetles get wrapped up into a bale of hay, quite by accident. Birds somehow just know that a beetle with this pattern should never be eaten, and they leave them alone. There are many, many species of Mylabris distributed across Africa, Europe and Asia.”  Once we had a genus name, we identified the species on Beetles of Africa and confirmed the identification on iSpot.

Blister Beetle: Mylabris oculata
Blister Beetle: Mylabris oculata

Thank you! Yes I thought it was a rather stunning beetle.
– Tane

Blister Beetle: Mylabris oculata
Blister Beetle: Mylabris oculata

Letter 19 – Blister Beetle from Kenya


Subject: Mylabris (blister) beetle in Kenya
Location: near Malwea River, Rift Valley, Kenya
March 13, 2017 2:22 am
Dear Bugman
Attached, some photos of a blister beetle found near the Malewa River in the Rift Valley of Kenya. Can you identify the species?
Many thanks!
Signature: Rob

Blister Beetle

Dear Rob,
According to iSpot, the genus
Mylabris is now classified as Hycleus.  We do have several images on our site from Kenya that we identified as Mylabris (now Hycleus) oculata, and though they are similar to your individual, they do appear to be a different species.  We have not had any luck with a species identification for you, but perhaps one of our readers will provide a comment with a clue.

Blister Beetle

Dear Daniel
Thank you for your help.
Best regards

Blister Beetle

Letter 20 – Blister Beetle from India


Subject: Yellow & Black Beetle
Location: India
April 12, 2017 2:11 am
Can you please help me identify the bug below – shot in India?
Many thanks
Signature: John F

Blister Beetle

Dear John,
This is a Blister Beetle in the family Meloidae.  Though the markings are not exactly the same, it might be a color variation or a different species in the same genus as this unidentified Blister Beetle on India BioDiversity.  We believe it is in the genus
Mylabris based on images we have located online, including on Bold Systems Taxonomy.  Blister Beetles should be handled with extreme caution as they secrete a compound known as cantharidin that is known to cause blistering in human skin.

Hi Daniel
Thanks so much…I almost labelled it as a blister beetle…but as you say the markings are somewhat different.
Must also be a cousin of the Cantharides Beetle we used to get in Africa – which caused extreme blistering!
Thanks again and for such a quick reponse.

Letter 21 – Longhorn Beetle, NOT Blister Beetle from Spain.


Subject: I’m not sure which blister beetle this is
Location: Culebron Spain
April 15, 2017 9:18 am
Would you mind identifying this insect please, I found it in Culebron in Spain. Thank you
Signature: Lorna

Longhorn:  Vesperus species

Dear Lorna,
We have not had any luck in our first attempt to identify this unusual beetle.  While the head and body structure do resemble those of a Blister Beetle in the family Meloidae, the antennae seem  to belong to a member of a different family, Cerambycidae.  We are seeking other opinions.

Longhorn:  Vesperus species.

Thank you so much Daniel for replying to me, I’m getting quite excited now that it seems unfamilar to you, I don’t know much about insects but I couldn’t find it anywhere on the Internet and now I’m getting really interested in learning more about the wonderful strange things. Maybe it will be named after me ‘beetle Lorna’ I’m sure not but it’s a nice idea!!!

Eric Eaton Provides a Non-Conclusive Response
I have no idea.  I’m not even sure if it is fully formed.  Looks like it just molted into an adult, which means it could be almost anything.
author, Kaufman Field Guide to Insects of North America

Thanks Eric,
That makes sense about it being “intermetamorphal.”

Thank you Daniel! Nobody here in Spain knows what it is either.
Lorna Gardner

Update:  December 30, 2017
Thanks to a comment from Jeff E. we now know this is actually a Longhorn Beetle in the genus Vesperus.

Letter 22 – Blister Beetle from India


Subject:  Bug
Geographic location of the bug:  Walayar
August 26, 2017 7:19 AM
I just wanna know it’s name
How you want your letter signed:  No

Blister Beetle

Dear No,
This is a Blister Beetle in the family Meloidae, possibly
Mylabris pustulata based on images posted to Encyclopedia of Life where it states:  “Mylabris pustulata is a species of blister beetle belonging to the Meloidae family found in South Asia. Adults feed mainly on flowers from a wide range of plant families. The first larval instar is an active triungulin form that is a predator of soft insects such as aphids. While the young are often beneficial to crops by suppressing other plant feeders, the adults can be a problem when present in large numbers. Flower feeding leads to lower yield and this can be a problem in some leguminous crops. They are however easily controlled by manual collection.”


Letter 23 – Blister Beetle from Malawi: Synhoria testacea


Subject:  Large bright red beetle
Geographic location of the bug:  Limbe, Malawi
Date: 06/10/2018
Time: 06:47 AM EDT
Your letter to the bugman:  Hi, my mother found this beetle a few days ago. I cannot find a similar one on the Internet. It was long with large mandibles and scarlet.:  Allnutty

Blister Beetle: Synhoria testacea

Dear Allnutty,
The first thing we have to say is WOW, that is one impressive beetle.  Interestingly, as we began our research, we found this very beetle pictured on the Travel Malawi Guide site, but alas there was no identification.  Though its appearance is not typical of the family, the antennae caused us to ponder if this might be a Blister Beetle in the family Meloidae, and there is one North American species that has a similar large head and mandibles, the Big Eared Blister Beetle,
Cissites auriculata, which is pictured on BugGuide, so we started our more thorough search with the subfamily Nemognathinae.  That led us to the Researchgate and Meloidae of Namibia where Plate #6 pictures Synhoria testacea.  We verified that identification on iNaturalist where there are several wonderful images.  It is also pictured on What Species?



  • 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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