What Do Longhorn Beetles Eat? (You Will Be Surprised To Know)

Longhorn beetles can hollow out an entire tree! While the adults feed on nectar, the larvae are the ones who cause the real damage to trees. Let us find out more.

Long-horned or Longicorn beetles have an unusual eating pattern. The eating habits of these beetles can harm trees and are a significant cause of damage to hardwood forests.

Belonging to the Cerambycidae family of the Coleoptera Order, these Arthropods have over 35,000 species.

Despite their names, longhorn beetles do not have long horns. It is their distinctively large pair of antennae that gives them the look for which they are named.

Do Longhorn Beetles Eat? #1 Answer

What Do They Eat?

Longhorn beetles are herbivores and steer clear of insects and meat. They spend their lives living in trees and get all their nutrition from those very trees.

While most longhorned beetles chew on dead wood, there is one species – the Asian Long-horned beetle (Anoplophora Glabripennis) that has become a menace to hardwood trees in North America.

The adult beetles of this species have a particular affinity towards hardwood trees like maple, birch, willow, elm, poplar, ash, and many more.

They lay their eggs inside the tree barks of these trees. When the larvae come out, the hardwood around them becomes one of their favorite snacks.

Some of the other common things that longhorn beetles love to eat are stems of smaller plants, twigs, leaves, seeds, nectars, fruits, flowers, grass, fungus, etc.

Due to their ability to process dead wood and the insects that reside within it, they are often considered beneficial insects.

They thrive and flourish best amidst deep and dense forest areas with abundant plants and trees.

How Do They Eat?

The trunks and the bark are where the Asian Longhorned beetle larvae start their feeding frenzy from.

But slowly, they make their way inside and, over time, can reach the very core of the tree, hollowing it out from the inside.

The beetles burrow through the trunk to chew away the plant tissue while cutting the nutrition supply route to the other parts of the tree.

They excavated multiple tunnels during this period, creating large visible holes all along the trunk.

When the adult beetles come out of these holes, they also cause the plant sap to drip out of them, making life even worse for the tree.

Do Longhorn Beetles Eat? #1 Answer

Do They Eat Other Insects?

Longhorn Beetles do not feed on any insects or other living organisms except for wood. Most species of beetles are herbivores, and longhorns are not an exception.

However, not all beetles are pure plant eaters. Some beetle species, such as the Epomis beetles, can eat other insects and amphibians.

What Liquids Do They Consume?

Like all the other species on earth, Longhorn beetles have an affinity towards water. They consider moist wood as a good source to get this water.

This is probably the reason why longhorn beetles search for wet lumber first. Most adult longhorn beetles also love to sip on nectar and tree sap for nutrition.

Damage Longhorn Beetle Cause By Eating Wood

An infestation of longhorn beetles is one of the worst things to happen to a tree. These beetles are wood-boring pests and can dig deep tunnels into their trunks while scavenging through the wood tissue.

As the beetles continue to borrow the tunnels, they often leave an exit hole on the opposite side of the trunk that measures about 1/8th to 3/8th of an inch. This hole further oozes out tree sap, making the tree even more vulnerable to attack from other pests and diseases.

These beetles cut short the nutrition supply chain from the root to the rest of the plant. By eating the tissue midway on the trunk, they can make the higher sections of the tree wither away.

As the plant tissue rapidly degrades and decomposes, the overall structural integrity of the tree is significantly compromised, which leads to its untimely death.

Do Longhorn Beetles Eat? #1 Answer

Other Insects That Eat Wood

Longhorn beetles are not the only insect interested in attacking trees. Here, we have listed six other bugs that have similar eating habits.


Present since the Jurrasic age, termites are one of the most invasive insect species on the planet.

These insects thrive in colonies with clearly defined hierarchies and structures. The worker termites, using their strong mouths, tear apart and chew cellulose from wood. They collect it for their other brethren to eat as well.

Carpenter Ants

Interestingly, even though these pests are known for eating away wood, they do not technically feed on wood.

Instead, they chew the wood from old and dead logs to build interconnecting tunnels to lay their eggs.

Carpenter Bees

The solitary bees also chew wood from barks and trunks of trees to build their nests and lay eggs.

Horntail wasps

The horntail wasps bore tunnels into the trees to live in them rather than eat the tree tissue.

Instead, these wasps thrive on the fungus that proliferates among the eggs that they lay in the burrowed holes.

Powderpost beetles

The insect is named so because of the sawdust-like powder they leave behind as they bore holes into the wood.

The starch derived from the wood is primarily used to feed the larvae and help them grow for about a year.


Recognizable due to their long and narrow distinctive snouts, weevils thrive exclusively on rotten wood predigested by fungus.

Do Longhorn Beetles Eat? #1 Answer

Frequently Asked Questions

Do longhorn beetles eat plants?

Yes, Longhorn Beetles are strictly herbivores thriving on various parts of plants like leaves, stems, twigs, flowers, barks, grass, fungus, nectars, fruits, etc.
They have an affinity towards barks of large trees like birch, ash, willow, and poplar tree, among many more. Neither the adult beetles nor the larvae eat insects.

Are longhorn beetles harmful?

Though the longhorn beetles pose no threat to humans and animals alike, they are considered one of the worst invasive pests to trees.
They can rapidly destroy large trees by boring holes in them. Hence they can be regarded as harmful pests to the environment.

Can longhorn beetles bite

Longhorn beetles can bite humans. However, their bites are not dangerous. They might cause a bit of pain, but they should subside in a few days.
Even though these beetles are better known for staying away from humans, the occasional bad encounter can happen and leave you hurting.

Can longhorn beetles fly?

The Asian longhorn beetles can fly long distances of up to 8.5 miles when they are strong and well-fed. On average, these insects cover 1.4 miles.
Flying is one of the ways through which these insects can spread all over forests very quickly. That is why when an infestation is discovered, the best route is to completely remove entire trees from the area to protect the nearby trees and forests.

Wrap Up

Longhorn beetle Infested trees can die at a rapid pace.

The best solution to handling longhorn beetles is nothing but uprooting the trees they infest and not letting them spread. Since these bugs have no natural enemies here in the states, as of now, this is the only solution to stop them.

Hence, it is important for everyone to be vigilant and not let these insects impact our hardwood industry by reaching our hardwood forests.

Thank you for reading!

Reader Emails

Longhorn beetles can be quite destructive to trees, but apart from that, they are harmless creatures.

Read some of the emails from our readers who were concerned about what these bugs are eating, and see for yourself!

Letter 1 – Bug of the Month: February 2008 – Longhorned Borer Beetle: Tragidion peninsularum


I have a strange bug I found him in my backyard, in Murrieta California. Do you know who he is? Linda Hi Linda, My is this photo positively gorgeous, and the beetle itself is equally stunning. We finally located a matching image on BugGuide from Arizona, Tragidion annulatum. Margarethe Brummermann posted the following comment: “If I read the source correctly annulatum was the original name and is still used for the Southwest population, whereas peninsulare is a later split-off for the California and Baja populations.” We then followed a link to an image of Tragidion peninsularum. We are happy identifying your specimen as Trigidion peninsularum unless we are proven wrong. It is also the end of the month and time to select a Bug of the Month for February. We like to post timely sightings for that honor that will help readers with seasonal identifications. This species is a first for our site, and perhaps there will be additional sightings in California this year, so we are thrilled to make your Tragidion peninsularum the Bug of the Month for February 2008. We will write to Eric Eaton in the hopes that he will confirm this identification, and perhaps add some relevant information. Hi, Daniel: I can’t make a call on the longhorned beetle, other than to say the genus and gender are both correct…. Eric

Letter 2 – Long Horned Borer Beetle from Senegal: Analeptes trifasciata


Taken in Senegal on coast in 2001 This beetle was very “gentle and kind enough to pose for me by ruler. Had the appearance of being carved from wood – so wonder what it’s real name is? Thanks Bill Frisbie (I have a few more interesting ones too – but we can start here J) Hi Bill, We can tell you the family Cerambycidae, the Long Horned Borer Beetles, without doing any research. Species identification may take hours and prove fruitless as there is often not much information on exotic species easily available online. Update: (07/19/2008) Hi, Daniel: Good news! I got an identification for the longhorned beetle from Senegal. It has no common name, but it is a female Analeptes trifasciata, or something very closely related. Check this out: http://www.cerambycoidea.com/specie.asp?Id=34&Tipo=T&NPag=2 and see if you don’t agree. This is a great website for longhorned beetles if you are familiar with at least the subfamilies, but you are correct that it is time-consuming! Keep up the great work, and best wishes for the upcoming lecture at the Getty this week. Eric

Letter 3 – Lepturine Flower Longhorn and unidentified Blister Beetle


Unknown Ontario beetles I’m hoping you can identify these beetles I encountered when I was doing some photography north of Algonquin Park in Ontario. I am equally interested in bugs as I am photography so I am always looking for opportunities to photograph them when I am out shooting. Many thanks, Janet Nelson
Lepturine Flower Longhorn Blister Beetle
Hi Janet, We checked with Eric Eaton and he couldn’t conclusively identify your beetles based on the photos, but he did give us Families. One is a Lepturine Flower Longhorn, the one on the daisy, and the other is a species of Blister Beetle. Ed. Note: We just received this identification. (08/09/2005) identifications Hello – I was recently shown your site, and it is excellent. My specialization is longhorned beetles, and in cruising around I notice a number of incomplete or uncertain IDs for this family. I don’t know if you are interested in receiving this sort of input, but if you are, I offer the following additions to your identifications. The lepturine cerambycid is Strangalepta abbreviata, a common eastern species which frequents a variety of flowers as an adult. The larvae typically breed in decaying wood. Keep up the good work. You are a valuable resource. Cheers Frank Hovore

Letter 4 – Fearful Longhorned Borer Beetle from Africa


AFRICAN BUG WONDERED IF YOU COULD TELL ME ABOUT THIS BUG? FOUND IT IN AFRICA. Jonathan Milne Hi Jonathan, We can assure you that the Longhorned Borer Beetle, or Cerambycid, in your photo is quite aware it is about being devoured by a wild-eyed, sharp toothed predator.

Letter 5 – Black and Orange Longhorn Beetle


Longhorn beetles on Agave Yo, Bugman! I sent this earlier, but am not sure it made it where it was trying to go. Anyhoo, I snapped this image a few weeks ago in the western foothills of the Galiuro Mountains of s. Arizona. I was shooting blooming Agave chrysantha and noticed what I thought at the time were tarantula hawks on the undersides of some of the flower umbels. I didn’t realize until I had the image blown up on my desktop that they were longhorn beetles. Given the location, any idea as to species? They seem to be chewing on the pedicels right at the flowers, maybe for the very sugar-loaded sap? Thanks! Dan Wolgast Aravaipa Canyon, AZ Hi Dan, This sure looks like a Black and Orange Longhorn, Tragidion coquus, or perhaps Tragidion armatum. According to Eric Eaton on BugGuide: “I understand that this genus, Tragidion, are mimics of tarantula hawk wasps.”

Letter 6 – Flower Longhorn Beetle


Can you identify this bug? Hi Can you please tell me what this bug is? They are all over my roses!!! I live in southwest Virginia. Thank you J wood Hi J., This is Strangalia luteicornis, one of the Flower Longhorn Beetles that mimics wasps. It takes pollen and nectar from flowers and the larvae feed on rotting wood. It is not a troublesome species and you need not worry that they are all over your roses.

Letter 7 – Long Horned Borer Beetle: Stenelytrana emarginata


Beetle ID We’re in upstate New York and moved to the country a couple years ago. Although we’ve seen some odd bugs this is the winner by far! It was beautiful and creepy all at the same time. Quite large at about 2” or more and a great flyer but it wouldn’t leave us alone – not in a menacing way. We would catch it and let it go on the other end of the deck but it would come right back where we were sitting. We had no food out with us but it certainly wanted to be near us. I really didn’t want to kill it so we let it chase us inside. We would love to know what it is. Seems to be a beetle of some type but I couldn’t find anything similar on the internet. Sorry for the poor photo quality – what do you expect from picture phones… Thanks for the help… Lisa in Staatsburg, NY Hi Lisa, A poor photo is generally better than no photo. We can tell you for sure that this is a Long Horned Borer Beetle in the family Cerambycidae. There are several species with this general coloration, so exact species identification is not likely. With that said, we are relatively sure this is Stenelytrana emarginata thanks to an image posted on BugGuide.

Letter 8 – Irish Long Horned Borer Beetle


Found in limerick ireland Hi, I found this beetle in my garden in Limerick in Ireland and wondered could you help me identify it?? Thanks Chris Hi Chris, We believe we have correctly identified your Long Horned Borer Beetle in the family Cerambycidae as Leptura quadrifasciata.

Letter 9 – Long Horned Borer Beetle


Nice antennae Wed, Oct 15, 2008 at 5:03 PM What IS this? We shared our picnic table with it stopping for lunch on a long road trip from Texas to Oklahoma. Looks a little like a grasshopper, but I couldn’t easily identify it at bugguide.net . Love the antennae. Any idea? My four kids and I love bugs and your site. Thanks for all you do to keep our budding entomologists busy. Shannon South OK
Long Horned Borer Beetle
Long Horned Borer Beetle
Hi Shannon, This is a Long Horned Borer Beetle in the family Cerambycidae, most probably in the genus Monochamus.

Letter 10 – Long Horned Borer Beetle: Plinthocoelium suaveolens


Big bug June 10, 2010 His body is a little over one and a half inches long, a half inch thick, and his antennas are over 2 inches. He is mostly a metallic green with faded red over on his underside and under his wings. He is hard and stiff and makes a buzzing sound when he flies. We found him at midday buzzing around our plum tree. It is early summer. Just an answer. Central Texas
Plinthocoelium suaveolens, a Longhorned Borer Beetle
This beautiful Longhorned Borer Beetle, Plinthocoelium suaveolens, has no common name.  Several years ago, we proposed the common name Tupelo Tree Borer based on its food plant.
Tupelo Tree Borer, a name we propose

Letter 11 – Horse Bean Longhorn Beetle


Brownish and black flying beetle? Location: Tampa Florida October 2, 2011 2:12 pm Hello! I found this bug on my porch and managed to snap a picture before he flew away. I was hoping you could tell me what this bug is. The huge antennas and the bug itself really amazed me. Signature: Thank you, Amy Ryan
Horse Bean Longhorn Beetle
Dear Amy, We could have written you sooner with a general family identification since we were able to determine that this is a Longhorned Borer Beetle in the family Cerambycidae, but we thought your beetle was distinctive enough that we could easily identify it to the species level, however that proved to be more difficult than we anticipated.  We eventually matched your individual to images of the Horse Bean Longhorn Beetle or Long Jawed Longhorn Beetle, Trachyderes mandibularis, based on photos posted to BugGuide.  The wood boring larvae feed in hackberry, fig and citrus trees.  We only have a few other images of the Horse Bean Longhorn Beetle in our archives.

Letter 12 – Drawing of a Longhorned Borer Beetle


Subject: Old Bug Illustration Location: Unknown September 26, 2012 4:58 am It’s an old illustration by this gentleman named E.A. Seguy but its name is no where to be found! Please help! Thanks so much! Signature: Wai, from Singapore
Drawing of a Longhorned Borer Beetle
Dear Wai, This drawing represents a Longhorned Borer Beetle in the family Cerambycidae.  We cannot provide the species without a location, though an expert in the family might be able to provide more specifics.  Pure Green Magazine has this to say about E. A. Seguy:  “Rather than classify species, the illustrator E. A. Seguy sought to celebrate selected exotic creatures in which he found artistic inspiration. Imaginatively employing floral and zoological motifs, Seguy’s early designs are wonderful examples of the art nouveau style, which swept through Europe in the decades around the turn of the century.”  Insects.org reports:  “Numerous artists and designers throughout history have drawn inspiration for their creations directly from the unparalleled diversity and beauty present in nature. E.A. Seguy was one such designer who was prolific from the turn of the century through the 1930′s. He produced eleven albums of illustrations and patterns of which Papillons and Insectes were dedicated to insect subjects. E.A. Seguy was a masterful decorative artist who spanned the art eras of Art Nouveau through Art Deco. His graphic technique was achieved through hand coloring prints through numerous plate stencils.” Thank you so much for your response! Much appreciated! have a great day, Wai

Letter 13 – Female Longhorned Borer Beetle


Subject: Never seen this bug before Location: North east Ohio July 24, 2015 5:29 pm I’ve never seen this bug beforr. In my area. Signature: Kristen
Female Longhorned Borer Beetle
Female Longhorned Borer Beetle
Dear Kristen, This is a Longhorned Borer Beetle in the family Cerambycidae, and because of the presence of an ovipositor at the tip of the abdomen, we can tell she is a female.  There is not much detail in your image, but the ovipositor is rather distinctive, so we believe based on this BugGuide image, this might be Graphisurus fasciatus which looks similar and ranges in Ohio.

Letter 14 – Bug of the Month May 2019: Longhorn: Stenocorus species


Subject:  Some kind of borer beetle? Geographic location of the bug:  Napa Valley, California Date: 04/29/2019 Time: 06:04 PM EDT Your letter to the bugman — Hello! This morning I saw this beetle sipping from a tree. It’s the biggest one I’ve ever seen outside of a zoo, probably about half the size of my index finger. And looks to be pregnant too! Any idea what it could be? How you want your letter signed:  Christine
Longhorn:  Stenocorus species
Dear Christine, This is very exciting. We agree that this appears to be a Longhorned Borer Beetle in the family Cerambycidae, and the size you indicated is quite impressive.  We did not recognize this Beetle, and the width of the abdomen at the base of the elytra is considerably wider than the thorax, and the thorax is unusual in its shape.  On a lark, we decided to search Cerambycidae and Napa Valley and we found Vandykea tuberculata pictured on the Cerambycidae Catalog Search, and it does seem to resemble your individual.  We found a single posting on BugGuide and the common name Serpentine Cypress Long-Horned Beetle and the remark:  “on California’s “Special Animals” List.”  We believe this might be a very rare sighting, and we are seeking assistance from Eric Eaton and Doug Yanega to get their opinions.  We will get back to you on this.  We also have selected this posting to be the Bug of the Month for May 2019, and we really hope our initial research has produced a correct identification so we can research this species more.  If that is a correct identification, according to Nature Serve Explorer:  “Critically Imperiled” and “An extremely rare endemic restricted to serpentine cypresses in the Clear Lake area in Lake County, CA.
Longhorn:  Stenocorus species
Correction Courtesy of Doug Yanega Hi. This is a large female Stenocorus, either vestitus or nubifer. They are difficult to distinguish based on photos. Peace, Doug Yanega      Dept. of Entomology       Entomology Research Museum Univ. of California, Riverside, CA Ed. Note:  Of the two species, BugGuide has information on Stenocorus vestitus which states:  “hosts: Pinaceae (Pinus, Pseudotsuga, Tsuga); adults on flowers” Wow, thanks so much! It’s always exciting to see new bugs in the spring and summer. Christine

Letter 15 – Banded Longhorn


Banded Longhorn July 26, 2009 Here is a Banded longhorn, Typocerus velutinus. It was eating pollen and, or nectar. This is the first one of these I’ve seen. Terry Mound, MN
Banded Longhorn
Banded Longhorn
Hello again Terry, WE really appreciate receiving your image of a Banded Longhorn.  IT is not well represented on our website.  According to BugGuide:  “Larvae feed on decaying hardwoods such as oak, hickory. Adults usually found in daytime, but do come to lights, so probably somewhat nocturnal.
Banded Longhorn
Banded Longhorn

Letter 16 – Spined Oak Borer


Weird Bug I Found June 2, 2010 This insect flew into my house the other day and landed on the ceiling in my bathroom. I’ve never seen anything like it. Is this some kind of roach? It appears to be missing one of it’s legs, but it has six long legs, very long antennae, is a mottled olive green/brown/black color. The body measured about two inches, with another two inches or so taken up by the antennae. I live in the Pennsylvania/ Philadelphia area. Bugged in Philadelphia Pennsylvania
Spined Oak Borer
Dear Bugged in Philadelphia, This is some species of Longhorned Borer Beetle in the family Cerambycidae.  It looks familiar to us, especially because of the spines at the tail end of the elytra, but we did not have any luck this morning browsing BugGuide.  Perhaps one of our readers will be able to provide an identification while we are at work. We decided to give it one more try, and we believe this is a Banded Hickory Borer, Knulliana cincta, based on images posted to BugGuide. Correction:  Spined Oak Borer We received a comment that identified this Cerambycid as Elaphidion mucronatum, and so we verified that on BugGuide, which calls it the Spined Oak Borer. Another Possibility courtesy of Karl June 3, 2010 Hi Daniel: This is a confusing one. It looks a lot like a cerambycid that was posted previously on WTB and identified as a Spined Oak Borer (Elaphidion mucranatum; Cerambycinae: Elaphidiini). You can also check out this site. However, it also looks very similar to another species (or complex of species?) in the same tribe, Parelaphidion aspersum (=Hypermallus compactus =H. flumineus =H. incertus externus). One site actually listed at least a dozen synonyms and it looks like a number of species have recently been re-assigned to the new species Parelaphidion aspersum. Predictably, the appearance is highly variable. One of the images on the Bugguide, originally posted on the dpughphoto site looks particularly similar to the one posted by Bugged in Philadelphia. I believe the Spined Oak Borer is smaller (< 1 inch?) and in most photos it appears too reddish. I am inclined to go with P. aspersum but I will let you make the call. Regards. Karl

Letter 17 – Six Banded Longhorn: Endangered Species


Black/yellow beetle w/ long antennae June 26, 2010 Found this one running around on the ground and on a tree in the woods in central MO, very active (couldn’t get a good shot because he wouldn’t stop moving!). I’ve trawled bugguide.net and can’t seem to get any closer than “Cottonwood Borer” or “Longhorn Beetle”, neither of which seem like a match. Can you help? Love this site, I’m going to add a link to my blog (“Mycologista”). Mycologista Boone County, Missouri
Six Banded Longhorn
Dear Mycologista, Thanks for the compliment.  You had classified this beautiful beetle into the correct family Cerambycidae, but that is a large family to sort through even on a site as comprehensive as BugGuide.  Your beetle is a Six Banded Longhorn, Dryobius sexnotatus, and according to BugGuide, it is:  “Uncommon and listed as rare and endangered on several websites. No way! Cool (well, not cool that it is endangered, but cool that I got to see one)!

Letter 18 – A different Banded Longhorn


Longhorn Beetle Location:  Fairfield, Maine USA August 23, 2010 1:42 pm Dear Bugman, I think I found a Flower Longhorn Beetle (Stictoleptura canadensis) on my Land Cruiser. I wonder why it was so far from the meadow and flowers…Can you please confirm/dis-confirm the I.D. and share any interesting info about this beetle? Thank you, James R
Banded Longhorn
Hi James, We agree that your beetle is Stictoleptura canadensis, and the BugGuide information page is noticeably lean on information.  It is a Flower Longhorn which means that though the larvae are wood borers, the adults feed on pollen.  The data page on BugGuide indicates the species is found in both eastern and western North America from Canada to Arizona.  According to the Cirrus Image website, the species is called the Banded Longhorn.
Banded Longhorn
Strange, I thought this (see attached) was the Banded Longhorn because of this image I found on B.G… I guess the names are a little general? Thank you, James Hi James, Common names do not have the rigorous degree of regulation that scientific names have, though because there are not many fact checkers, there are often incorrect identifications posted on the internet.  That is why we like to have “credible” websites for our links.  The link you provided is an unidentified Longhorned Borer Beetle, but we followed information on the page to the bugGuide information page for the Banded Longhorn, Typocerus velutinus.  If BugGuide is using the common name Banded Longhorn, it must be an officially accepted common name. Hello Daniel, Wow, thanks for the info and the additional identification! It’s incredible that so many bugs and insects are even identified, at all. Best regards, James

Letter 19 – Black and Yellow Longhorn Beetle from England


Subject: Asparagus Beetle Location: Kent England May 8, 2014 8:09 am Hi Could you tell me whether this is ask asparagus beetle. We think it came out of the shopping! Many thanks Signature: Simon
Black and Yellow Longhorn Beetle
Black and Yellow Longhorn Beetle
Hi Simon, This is not an Asparagus Beetle, but rather one of the Longhorn Borer Beetles in the family Cerambycidae.  We have identified it as a Black and Yellow Longhorn Beetle, Rutpela maculata, thanks to Ray Wilson’s Bird and Wildlife Photography website.  According to UK Safari:  “This species is nearly always spotted feeding on nectar on flower heads such as hogweed or cow parsley.  The larvae feed on rotting tree stumps, especially birch and pine.” Hi Daniel Thank you so much for your research and the time spent. Best wishes Simon

Letter 20 – Two Banded Longhorn from Ireland


Subject: Long beetle shaped bug Location: Ireland May 23, 2015 2:01 am Hi I found this bug in my bathroom and I can’t figure out what he is, you might even say it’s bugging me, if you’ll excuse the pun. Anyway I’d appreciate if you could identify, thanks xx Signature: bugged out
Two Banded Longhorn
Two Banded Longhorn
Dear bugged out, We quickly identified your Longicorn from the family Cerambycidae on Nature Spot as the Two Banded Longhorn, Rhagium bifasciatum.  It is described as “A large species of longhorn beetle that may reach 22 millimetres long and can be distinguished by the two prominent pale yellow bands on each elytron” and the life history is described as “Like other longhorn beetles, R. bifasciatum lays its eggs in dead wood, often using coniferous trees, where they bore deep, broad tunnels until they are ready to pupate after about two years.”  According to Eakring Birds:  “Another fairly distinctive Longhorn beetle is Rhagium bifasciatum. The larvae develop under bark and we have found newly hatched adults in the early Spring, under Pine logs at Clipstone Old Quarter. The adults are commonly found on tree trunks and occasionally low vegetation. R. bifasciatum is a common beetle throughout the Sherwood Forest NNR.”

Letter 21 – Black and Yellow Longhorn from the UK


Subject:  Black and yellow bug Geographic location of the bug:  woodland, near Worcester,  uk Date: 06/25/2018 Time: 06:21 AM EDT Your letter to the bugman:  I’ve searched through photos on  uk bug ID websites but still haven’t found this one! Can you help please? How you want your letter signed:  Pippa
Black and Yellow Longhorn
Dear Pippa, You had most of the common name for this Longhorn Beetle in the family Cerambycidae in your subject line.  Called the Black and Yellow Longhorn according to UK Safari where it states:  “Rutpela maculata is also commonly known as the ‘black and yellow longhorn’ for obvious reasons. It can be identified by its tapered wing casings which feature four black bands that are complete at the rear end but are broken nearer the thorax.  The four front legs are yellow with black tips.  The hind legs are mostly black.  This species is nearly always spotted feeding on nectar on flower heads such as hogweed or cow parsley.  The larvae feed on rotting tree stumps, especially birch and pine.”  Encyclopedia of Life uses the common name Spotted Longhorn which is also quite descriptive.  According to Nature Spot:  “Common and widespread in England and Wales, much less common further north.” Wow!   That’s amazing – What service!  Thank you so much I am a wiser woman!

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 – Longicorn from China


Subject: Cicindela sp? Location: Laba He, Sichwan, China December 8, 2016 12:23 pm Dear Bugman! This time I have a few ”bugs” fron SW China which I visited during october 2016. First bug is probably a Cicindela. Sadly I did not take any photos with reference object, which of course would have been good. This species´ body is about 1½ times Cicindela sylvatica. In other words around 30 mm. I was photographed in Laba He Nature Reserve in Sichwan, China at the altitude of about 1200 – 1500 metres asl. Signature: slit
Dear Slit, This is NOT a Tiger Beetle in the genus Cicindela as you suspect, but rather a Longicorn or Longhorned Borer Beetle in the family Cerambycidae.  Unfortunately, we cannot provide you with a species or genus at this time.
Identification courtesy of Karl Hello Daniel and slit: There are several longicorns in the genus Anoplophora that look very similar to this one. I think A. coeruleoantennata (Cerambycidae: Lamiinae) is the closest match. Regards. Karl
Update Location: Sichuan (page 23) 2016-01-12 January 13, 2017 12:24 am Dear BugmaA few weeks ago I posted a Longicorn on this page. A “Karl” commented on it and suggested it may very well be a Anophlophora coeruleogantenata ! I have googled on this species but not been able to find it. I wonder if it might be a synonym. I would like to et in contact with this Karl for further information. Can you please either send me his mailadress, or send my mailaddress to him, with my request? I would appreciate it. my mailadress slithner@outlook.com Signature: To “Karl” Hello again Slit, We wonder perhaps if you could not locate information because of an incorrect spelling.  Anoplophora only has one “h”. No that´s not the solution. I also got the suggestion Anplophora glabripennis which is easy to find. Have you got any link you can suggest for A. coeruleogantenata? I have tried on both Google Chrome and Internet explorer. I have looked at images of A. glabripennis, but I doubt that is the one. Cheers Stefan here is this link that Karl originally provided where we learned an alternate species name is “Melanauster coeruleoantennata Breuning”. https://apps2.cdfa.ca.gov/publicApps/plant/bycidDB/wdetails.asp?id=32215&w=o

Letter 2 – Unknown Longicorn from New Zealand


Subject: Longhorned like bug Location: Auckland January 26, 2017 1:10 am Hello, found this guy in the house. Unfortunately it’s dead, but I’m still interested to know what it is. Signature: Lisa
Dear Lisa, This is a Longhorned Borer Beetle or Longicorn in the family Cerambycidae, but we are not certain of the species.  There are very few species identified on the Landcare Research Manaaki Whenua site.

Letter 3 – Round-Headed Borer from Spain


Subject: Bugs on Quercus ilex (Spain) Location: Salamanca (Spain) February 20, 2017 6:14 am I enclose three pictures of two bugs (larva and adult) found on young Quercus ilex (inside). The larva is about 25 mm and de adults about 2 mm. They were found in Salamanca (central western Spain). They don’t look like the usual borers in the area. Thank you very much Signature: Luis Carlos Jovellar (Salamanca, Spain)
Round-Headed Borer
Dear Luis, The images of the larva you submitted appear to be Round-Headed Borers, a general name for the larvae of members of the Longhorned Borer Family Cerambycidae.  See this BugGuide image for comparison.  They are unrelated to the adult insects you submitted which we will address at a later date.  Knowing the host plant is often a tremendous assistance in the identification of larval stages.  According to the opening sentence of a scholarly article we located on Springer Link:  “Cerambyx welensii Küster is one of the greatest threats to Quercus suber L. and Quercus ilex L. in Spain.”  While that is not a definitive identification for the Round-Headed Borer you sighted, chances are good that it might be a correct identification.  iNaturalist has an image of the adult.  Your larva has a distinctive yellow coloration.  The Espiritu de Arbol blog has images of adults and larvae. Dear Daniel, Thank you very much for your help. Although presence of Cerambix is common in this area, I had never seen a larvae in such a thin branch, hardly bigger in diameter than the larvae itself. Best regards Luis Carlos Jovellar

Letter 4 – Round Headed Borer


Subject: Firewood Location: BC Canada March 1, 2017 1:57 pm Hi 🙂 can you tell me what kind of bug this is . I live in the Canadian Rockies . These are all over n my firewood . This guy is about an inch long he was sleeping or frozen but now that he is warm , he is very much alive ? Signature: Rhonda
Round Headed Borer Grub
Dear Rhonda, This is the grub of a wood boring beetle, and we strongly suspect it is a Round Headed Borer Grub from the Long Horned Borer family Cerambycidae, but we cannot provide a species identification for you. Thank you so much 🙂 I just went and looked at more pictures and info . Super happy they are not termites . I still feel a bit sad that many do probably die in the fire ?

Letter 5 – Longicorn from Mississippi is Cypress Bark Borer


Subject: Long-horned borer? Location: Lamar Co., Mississippi, USA June 16, 2017 8:51 pm A friend of mine in Lamar County, Mississippi sent this photo for id as she thought it was a pretty interesting bug. The closest I could come up with was the red-headed ash borer, and I’m certain that isn’t it. Who is this beetle? Should my friend be worried about her timber? Signature: J Kyzar
Cypress Bark Borer
Dear J Kyzar, You are correct that this is a Longhorned Borer Beetle or Longicorn in the family Cerambycidae, but it is not a Red Headed Ash Borer, though we believe it is a member of the same subfamily Cerambycinae.  We have not had any luck scouring either BugGuide or Arthur Evans’ excellent book “Beetles of Eastern North America”, so we have reached out to both Arthur Evans and Eric Eaton for assistance.  We hope to have a response for you soon.  The swollen femora and basal antennae segments are very distinctive, as are the color and markings.  We don’t know how to search the database on the Mississippi State University Cerambycidae of Mississippi page, but we did try to contact curator Terence Schiefer for assistance as well.
Cypress Bark Borer
Arthur Evans Responds. Where is it from?  Sorry! I seen now that it is from Mississippi. Checking… http://bugguide.net/node/view/573634
Cypress Bark Borer
Dear Arthur, Thanks so much for identifying the Cypress Bark Borer, Physocnemum andreae.  It is interesting that there is only one image on BugGuide from South Carolina and the site states:  “uncommon.”  The images of mounted specimens on Cerambycidae Species are very detailed. Eric Eaton Responds Wow!  Maybe the person can post these images to Bugguide?  There is only one image for the species right now. Eric author, Kaufman Field Guide to Insects of North America http://bugeric.blogspot.com/ Thank you so much! I have a moderate background in entomology (I used to work with plecopterans) and when my friend asked for an ID on Facebook I turned to your site and bug guide. Much to my dismay I couldn’t find anything that matched! I have a few other images of the beetles and I’ll head on over to bug guide and submit them. Thanks! J Kyzar

Letter 6 – White Oak Borer, we believe


Subject: Borer Beattie? Location: Warrenton, va June 24, 2017 6:52 am We found this bug on a family adventure today. Can you help us identify? Signature: brooks family
White Oak Borer, we believe
Dear Brooks family, You are correct that this is a Borer Beetle, and it is a Flatfaced Longhorn in the subfamily Lamiinae.  We believe we have correctly identified it as a White Oak Borer, Goes tigrinus, thanks to Arthur Evans excellent book Beetles of Eastern North America, and we verified that by matching your individual to this BugGuide image.  According to BugGuide:  “Widespread, but uncommon in e US (TX-FL-NY-MI)” and “Very uncommonly collected although widespead and reportedly an important pest of all oaks in the white oak group.”

Letter 7 – Longicorn from Hong Kong: Olenecamptus sp.


Subject: Found this on my balcony in Hong Kong Location: Hong Kong June 30, 2017 1:54 am Hi i just saw this bug on my balcony in Tai Hang, Hong Kong. What is it? Signature: MC
Dear MC, We love your image, but alas, the best we can do at this time is provide you with a family.  This is a Longicorn in the family Cerambycidae.  Perhaps one of our readers will be able to provide a species name.

Letter 8 – White Oak Borer, but with whose eggs???


Subject: white oak borer with eggs Location: Troy, VA July 3, 2017 11:32 am I took this photo and when I looked more closely I discovered there were eggs in the picture. I don’t know if the eggs are from the beetle or the other bugs that were nearby. I believe this to be a white oak borer. (I just sent another image and should have mentioned that I don’t think the giant beetle in the photo is a hercules beetle. I hope you have time to take a look at it.) thanks again Signature: Grace Pedalino
White Oak Borer
Dear Grace, Thanks for sending in your image of a White Oak Borer.  We do not believe the eggs belong to the Borer.  We believe the eggs are Tiger Moth Eggs.

Letter 9 – Palmetto Longhorn


Subject: What’s that bug! Location: South west Florida, USA July 4, 2017 11:08 pm I found this insect down in south Florida. I’ve looked all over for a name and can’t find it! Help Signature: Bug masters
Palmetto Longhorn
This Palmetto Longhorn or Cabbage Palm Longhorn, Osmopleura chamaeropis, is pictured on BugGuide where it states:  “This species is rarely collected but can be locally abundant (Turnbow & Hovore 1979).”  

Letter 10 – Unknown Longicorn


Subject: What is this?? Location: New Hampshire July 3, 2017 12:37 pm Found in our house in southern New Hampshire in July. Approximately 1 inch long. What is it? Signature: Katie
Dear Katie, This is a Longhorned Borer Beetle or Longicorn in the family Cerambycidae, but we need additional time to identify the species.  Perhaps one of our readers will write in with an identification.

Letter 11 – Flower Longhorn: Lepturobosca chrysocoma


Subject: Beetle in Yosemite Location: Yosemite National Forest, July 19, 2017 5:18 pm I was hiking up to sentinel dome when I noticed this beetle resting upon this grouping of small flowers. I cannot seem to to find this type of beetle on any identification chart. Signature: I’m not sure what this means
Flower Longhorn
This is a Flower Longhorn in the subfamily Lepturinae, but we have not been able to quickly identify the species.  We are posting your submission as unidentified and we will continue to research this matter.  Perhaps one of our readers will be able to comment and provide an identification. Ed. Note:  Thanks to Cesar Crash of Insetologia who identified Lepturobosca chrysocoma for us.  According to BugGuide:  “The very dense, appressed, metallic golden pubescence is distinctive” and “Larvae eat decaying wood, both hardwoods and conifers.”


  • 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.

  • 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.

22 thoughts on “What Do Longhorn Beetles Eat? (You Will Be Surprised To Know)”

    • Thanks Cesar,
      I posted really quickly yesterday because I had to leave extra early for work and I didn’t have time to research, but it was such a lovely image.

  1. I just found one of these in my south Florida home but it was a decent 2+ inch and when I put a cup over it,it began hissing at me it sounded like pressure being released from a small cylinder like it was spraying. That noise coupled with the nail in the wall I thought this thing was super mutant and mounting deep in my wall. Has anyone heard of this creature hissing or know a variant that does his and is 2x normal size

    • The hissing sound you describe is known as stridulation, and many Beetles, including Scarabs and Longhorns, are capable of stridulation.

  2. Hi guys, I live in the south of Chile and have found grubs that look just like this eating the inside of my two Blackcurrant bushes. They even have the same bright yellow coloring. I have removed and destroyed the bushes, but have two of these guys in a jar to take pictures.

    • Bycids have strong mandibles and they might bite, and the bite might hurt, but Bycids are not dangerous to humans.


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