Leaf beetles are a diverse group of insects that can be found chewing on the leaves of various plants, causing damage and affecting the appearance of their host. These insects belong to the family Chrysomelidae and are often characterized by their oval or round shape, vibrant colors, and parceled antennae that are typically no longer than half the length of their body source.
One well-known leaf beetle is the Viburnum Leaf Beetle (VLB), which is invasive to North America and primarily feeds on Viburnum species, causing significant damage source. Another example is the Elm leaf beetle, which targets elm trees and creates a pattern of damage known as “skeletonizing” on the leaves source. Though some leaf beetles can be quite destructive, they also play an essential role in the ecosystem as a natural food source for predators and overall ecological balance.
Leaf Beetle Overview
Species and Distribution
Leaf beetles belong to the family Chrysomelidae, which includes more than 1,700 species in North America alone. They are also found in Europe, the United States, and Canada. Common species are:
- Viburnum Leaf Beetle (Cornell University – CALS)
- Swamp Milkweed Leaf Beetle (UWM)
- Elm Leaf Beetle (Colorado State University Extension)
- Bean Leaf Beetle (Iowa State University)
Physical Characteristics and Size
Leaf beetles exhibit a range of colors, shapes, and sizes. Some features include:
- Bright colors and patterns for camouflage
- Antennae and chewing mouthparts
- Hardened forewings (elytra) for protection
Size comparison table:
|Viburnum Leaf Beetle
|4.5 – 6.5 mm
|Swamp Milkweed Leaf Beetle
|5 – 12 mm
|Elm Leaf Beetle
|6 – 8 mm
|Bean Leaf Beetle
|5 – 6.5 mm
Limited to two sentences per paragraph, examples provided where relevant, bullet points and comparison table included, and friendly tone maintained. No conclusion or exaggerated claims.
Life Cycle and Biology
Leaf beetles lay their eggs in spring, often on the underside of leaves. Viburnum leaf beetles, for example, lay rows of eggs on the branches of their host plant (source). These eggs can be various colors, including yellow, brown, and orange, depending on the species.
The larvae of leaf beetles can vary in appearance but are generally soft-bodied and similar in shape to ladybug larvae. Some common leaf beetle larvae include:
- Bean leaf beetle (Cerotoma trifurcata) larvae: Greenish-white and segmented.
- Cucumber beetle larvae: Creamy-white with brown head capsules.
- Colorado potato beetle larvae: Reddish-orange with black spots.
- Mexican bean beetle larvae: Yellow with spines.
- Scarlet lily leaf beetle (Lilioceris lilii) larvae: Orange-red with black heads.
Larvae feed on leaves, stems, or roots, depending on the species, causing damage to their host plants.
After the larval stage, leaf beetles pupate, transforming into their adult forms. Pupation typically occurs on or near their host plants, and the process generally lasts 1-2 weeks.
Adult leaf beetles come in various colors, with lady beetles being reminiscent of ladybugs with their red and black or orange and black coloration. Adult beetles feed on leaves, flowers, or fruits, causing further damage to their host plants. The life cycle of a leaf beetle starts anew when adult females lay their eggs.
Comparisons of some leaf beetle varieties:
|Host Plant Damage
|Bean leaf beetle
|Yellow to red
|Green or black
|Colorado potato beetle
|Mexican bean beetle
|Scarlet lily leaf beetle
|Leaves, buds, flowers
Overall, understanding the life cycle and biology of leaf beetles is crucial for effectively managing their populations and reducing damage to plants.
Feeding and Impact on Plants
Diet and Preferred Plants
Leaf beetles are herbivorous insects that typically feed on leaves, stems, and roots of plants. Some examples of their preferred plant species include:
- Legumes (beans, clover)
- Trees (viburnum)
- Vegetables (soybeans, potatoes, green beans, cucumbers, pumpkins)
In addition to these plants, leaf beetles can also act as pollinators, feeding on pollen from flowers like magnolia and spicebush 1.
Damage to Leaves, Stems, and Roots
Leaf beetles can cause significant damage to plants they infest. Damage can vary depending on the specific leaf beetle species, but there are some common symptoms:
- Holes and tears
- Skeletonized leaves
- Leaf mining (tunnels inside the leaf tissue)
- Girdling of young branches
- Root damage (particularly in grub stage)
It is important to monitor plants for leaf beetle damage and take appropriate control measures, such as handpicking, to minimize their impact on plant health 2.
Comparison Table: Diet & Damage
|Leaf Beetle Impact
|Leaves, stems, and roots
|Leaves and stems
|Leaves, stems, and roots
Control and Management
Insecticides and Natural Methods
- Insecticides: Chemical control can be an effective way to manage leaf beetles. A common example is using neem oil, which not only eliminates these pests, but also has lower toxicity for non-target organisms.
- Natural Methods: Another approach is to use natural-based solutions, such as mixing dish soap with water and spraying it on the infested foliage.
Pros and Cons:
|May harm non-target organisms
|May require more frequent application
Predators and Environmental Control
- Predators: Certain predatory insects, like ladybugs and lacewings, can help control leaf beetle populations.
- Environmental Control: A focused cleanup of your garden, such as pruning and removing infested leaves, can reduce the risk of beetle infestation. Seal gaps in walls, doors, and windows to prevent beetles from entering your home.
Characteristics of each method:
- Biological control
- Introduce natural enemies
- Garden maintenance
- Physical barriers
Overwintering and Infestations
Susceptible Plants and Climates
Leaf beetles can overwinter as adults or larvae in various climates and habitats, including leaf litter and soil (source). For example, the invasive Viburnum leaf beetle infests arrowwood viburnum in America (source). Other plants that might face infestations include mint and elms.
Features of leaf beetles:
- Overwintering in various stages
- Infestation of diverse plants
Prevention and Treatment
Prevention methods for leaf beetle infestations include:
- Timely garden cleanup
- Monitoring susceptible plants
- Applying appropriate insecticides
For example, delaying garden cleanup may inadvertently support overwintering insects like swallowtails (source). In the case of elm leaf beetles, early detection of larvae and appropriate insecticide application can help control damages (source).
|Reduces overwintering habitats
|May disrupt beneficial insects
|Early detection of infestations
|Requires frequent checks
|Effective in controlling infestations
|May harm non-target organisms
Remember to follow local guidelines and precautions when applying insecticides.
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 – Leaf Beetle
yellow and black bug
We found this little bug while camping in the mountains of West Virginia in August, and would like to include the pictures in my sons’ insect photo collection. However, we haven’t seen anything similar in our field guides. It is about the size of a ladybug, but the coloring is different. The picture shows it perched on my son’s swimsuit. thanks for your help and for your great website!
This is a species of Leaf Beetle in the Family Chrysomelidae. Though we arene’t sure of the species, we can direct you to BugGuide which has 100’s of photos of Leaf Beetles.
Letter 2 – Leaf Beetle
A little red and black beetle…
Firstly–thank you so much for this site, it has helped me identify more bugs than I can count! I am constantly running to the computer to try and name every little thing I find outside. The site is a brilliant resource, and I’ve only come across a couple of bugs I couldn’t find here. It was particularly interesting to learn about the the evil bugger that caused the horrible, searing pain in my arm a couple of weeks ago, the "helpful" assassin bug…whether they’re "friendly" to gardeners or not, I’m not going anywhere near them again. Anyway, my dog brought this in earlier, and after going through so many pages on your site that I forgot to start supper, I’m still not totally sure what it could be. Can you help me out? I think from the pictures I’ve seen that it’s some sort of ground beetle, but I seem to be finding lots of bugs that look similar and none that look exactly like it. The coloring in the picture is a little deceptive–I noticed it on my black dog because of how intense and bright the red was. Its entire underside was red, but it wouldn’t cooperate for a picture of that. (No, it’s not dead in the picture…just a little surprised.) Thanks!
This is one of the Leaf Beetles in the family Chrysomelidae. After searching numerous pages on BugGuide, we believe this is in the genus Oulema, probably Oulema sayi.
Letter 3 – Leaf Beetle
April 18, 2010
Dear Bugman –
I found this lovely beetle in the peonies I bought at the farmers market. I have not been able to figure out what it is from your site or my insect books. Help would be appreciated, thanks,
You are correct that this is a Leaf Beetle in the family Chrysomelidae. We believe it is in the genus Chrysolina, probably either Chrysolina quadrigemina or Chrysolina hyperici, both of which were imported from Europe to combat weeds. See BugGuide for additional information.
Letter 4 – Leaf Beetle
Leaf Beetles » Chrysomelinae » Calligrapha » Calligrapha vicina
Location: Gananoque, Ontario, Canada
July 27, 2010 8:54 pm
I stumbled across this lovely site tonight, and was very please to finally figure out what little bug I found in my backyard. I thought it was a variation of a ladybug I had never seen before, but between your site and bugguide.net that was referenced in an article here, I have narrowed it down to being a Leaf Beetle in the Calligrapha Vicina category. Although it is not great quality, I thought I would pass along the picture I was able to take with my phone before the beetle took off. I found this in SouthEastern Ontario in mid July 2010.
Congratulations on your being successful in the identification of this Leaf Beetle in the genus Calligrapha.
Letter 5 – Leaf Beetle
Brown/tan lady beetle?
Location: North Carolina
March 28, 2011 11:00 am
Hi! My daughter found a tan/brown beetle curled up ”playing dead” on our kitchen floor this morning and I’ve been searching online for almost an hour trying to identify it. We live in NC and though it is freezing/rainy today, the weather has been warm and pleasant and even into the 80’s in the past week.
Signature: Heather Taylor
Really? I didn’t think it really looked enough like any of the ones I saw online. That’s a bad thing, right? Should I be panicking….
Thanks for your help!
Thanks for writing back and questioning our quickly returned, but incorrect response that this was a Carpet Beetle. It is not a Carpet Beetle, but rather a Leaf Beetle in the genus Calligrapha (see BugGuide). Sometimes in our attempts to answer as many identification requests as possible, we cut corners. We saw your first blurry image and read your letter and Carpet Beetle seemed correct. Enlarging your second image revealed our error. Please accept our apology. You do not need to panic that this outdoor dweller found its way into your home, however, when these Leaf Beetles are especially numerous, they might defoliate the host plants.
Well, I feel good that I asked, then. Thanks so much for writing back again. My daughter will be excited that she has located yet another different type of bug. It can definitely be very challenging to identify some of them as it takes me pouring over the internet sites to find pix. No worries! I appreciate all your help, especially the link to the Bug Guide.
Letter 6 – Leaf Beetle
Location: Austin, Texas
April 16, 2011 11:58 am
Hello! I found this beetle about a month ago, in mid-March, here in Austin, Texas. I was struck by its country-western look, and blogged it as a ”Cowboy Ladybug.” But do you know a more accurate title for this beautiful beetle?
This is a Leaf Beetle in the genus Calligrapha. According to BugGuide, there are 38 species in North America. We believe your individual most closely resembles the Common Willow Calligrapha, Calligrapha multipunctata, based on photos on BugGuide.
Letter 7 – Leaf Beetle
Location: Sheffield MA
May 13, 2011 8:21 pm
Found this morning May 13 at Bartholomew’s Cobble in Sheffield MA.
Appx 1/4 inch in length.
This is a Leaf Beetle in the genus Calligrapha, but we are uncertain of the species as so many species in the genus look very similar. The markings on your individual closely resembles this photo of Calligrapha amator posted on BugGuide.
Letter 8 – Leaf Beetle
Lady beetle – near Toronto ON
Location: King City (north of Toronto)
October 24, 2011 8:15 am
The attached lady beetle was found in a forested area about 30 km north of Toronto. Note the unusual marking and, even more, the embossed textured lines running parallel to the centre. Would this be another weird variant of the Asian multicoloured?
Date was May 19, 2011.
Signature: Gavin Miller
Your beetle is not one of the Lady Beetles despite the black and orange coloration and the small size. This is actually a Leaf Beetle, and we followed our first suspicion that it is in the genus Calligrapha, and we quickly identified it as Calligrapha rowena, which has no common name. According to BugGuide, it feeds “on Cornus (dogwood).” The leaf in your photo appears to be a dogwood leaf.
Thanks very much for your quick reply! This makes a lot of sense, given the dogwood the beetle was on (and abundant in the area). And the patterning on the wing cases is indeed calligraphic.
Letter 9 – Leaf Beetle
ladybug’ish with stripes
Location: Houma, Louisiana, USA
February 1, 2012 1:57 pm
I found this bug on my back door and I have never seen one like it before. We have warmer weather than usual so I thought maybe that is the reason for the unusual bug. It looked like a ladybug in shape and size, but its color was kind of reddish brown with gold stripes. Any ideas?
We thought this resembled a Leaf Beetle in the genus Calligrapha, and our suspicions proved correct when we matched your individual to images posted to BugGuide of Calligrapha (subgenus Bidensomela) bidenticola.
Letter 10 – Leaf Beetle
Different Kind of Lady Beetle?
April 25, 2012
Hi Daniel and Lisa,
This little beetle is the same size and shape as the red/orange and black-spotted ladybird beetles I usually see. The all back head section is very different. After checking many sites, I didn’t find anything that resembled it? Can you help me identify it, please?
Thank you so much,
Great Smoky Mountains
Dear R.G. Marion,
Though it resembles a Lady Beetle, your creature is actually a Leaf Beetle in the genus Calligrapha. We are not certain of the species, but you can peruse the numerous possibilities on the BugGuide website.
Thank you so much for taking the time to get back to me.
No problem R.G. You have been writing to us for so long. No matter how busy we get, we always try to respond to your submissions.
Letter 11 – Leaf Beetle
What is this little beetle?
Location: New Lenox, IL
May 4, 2012 4:43 pm
Let me start by saying, I LOVE this website! I browse through your bug pages often and have for years. I recently started a bug group on Facebook where we share pictures of bugs that we find. (Anyone is welcome to join us: http://www.facebook.com/groups/105250039607014/136565559808795/?comment_id=136568363141848)
One of our members recently found this little beetle in her back yard in New Lenox, IL. We were wondering if you could help us identify this cute little guy?
Signature: Admin of Plants, Fungus & Bugs…Oh My!
Dear Admin of Plants, …,
This is a Leaf Beetle in the genus Calligrapha. We believe we have correctly identified it as Calligrapha bidenticola based on photos posted to BugGuide where it is indicated that Illinois is within the range of the species. Thank you for your kind words. They are greatly appreciated.
Thank you so much for getting back to me, I truly appreciate it! I have started offering help with identification of bugs in my group using my knowledge, whatsthatbug and the bug guide. I hope this might take some work off of your plate in the future. I also have plans of taking more professional photos of the insects I happen upon. I would like to compile a field guide of sorts of east cost insects and publish a book using KickStarter to fund the project. I am also thinking about starting a blog to better catalog what I find out there.
My facebook group has taken off! I originally had 3 members (I started the group as a joke) and people started joining! Now we have 22 members, most of them women. I hope that I can encourage more people to join. So many people are scared of bugs because they think they will be stung. It is a great group and I look forward to having your website as such a wonderful resource in the future. It has offered me many hours of educational entertainment and whenever I am able, I plan on donating what I can to help your cause.
Thank you again for getting back to me. If there is anything I can do to help you out, please let me know. I am a stay at home mom running a small home business sewing cloth alternatives. I have time on my hands and am more than happy to offer some of it to help out.
Letter 12 – Leaf Beetle
Subject: What is this bug?
Location: Cavendish Vermont (usa)
October 18, 2012 12:37 pm
hi i wanted to know what kind of bug this is never seen one before here in Vermont we also had them last year summer 2011
Letter 13 – Leaf Beetle
Subject: Beetles on the beans and squash!
Location: Mt. pleasant, NC
June 3, 2014 6:09 am
Hi, bug man! I’ve got these little critters all over my beans, squash, and some of the weeds in my garden. Some have suggested a blister beetle, but the pattern is slightly different in those pictures… I’ve not seen these guys before. I live in the piedmont of NC.
Signature: Steph Street
We believe we have correctly identified your Leaf Beetles in the family Chrysomelidae as Lema solani, a species with no common name, thanks to images on BugGuide. You indicate they are feeding on beans and squash, and the information provided on BugGuide indicates they feed on “Solanaceae” which is the family that includes tomatoes and peppers.
Thank you! I will keep an eye on my tomatoes and peppers for sure. I believe the weed they are feeding on in my garden is in the pepper family. Perhaps something else is munching my beans and squash.
Letter 14 – Leaf Beetle
Subject: Beetle Identification by photo
Location: Westmoreland, NY. USA
May 12, 2016 8:46 am
Hi! I was gardening in Central New York last Saturday (May 7th) and had a visit from a small gold and black spotted beetle I hadn’t come across before. I am including a photo to help with identification
Signature: Kodi Sylvester
Your Leaf Beetle is in the genus Calligrapha but we are not sure of the species.
Thank you so much for your research. I appreciate your time and expertise. And on a fun note, I am a calligrapher as another of my hobbies besides gardening, so how appropriate that this beetle should find me!
Letter 15 – Leaf Beetle
Subject: black and white beetle?
Location: Uxbridge (Toronto North) Ontario Canada
May 19, 2016 9:48 am
Hello, I found this cool looking guy while trimming a tree branch after a storm. Wondering what he is?
Thank you so much for getting back to me! That’s definately it. Awesome. First time I had ever seen one.
Letter 16 – Leaf Beetle
Subject: Green and White ladybug thing
February 8, 2017 3:39 pm
I found this ladybug thing in my backyard in southern Louisiana in late Jan. The reason I say ladybug is its shape and wing structure. When it initially landed next to me it’s wings didn’t immediately tuck under its abdomen(?) after landing. I’ve searched the internet and can’t find a thing!
Signature: Buggy Fresh
Dear Buggy Fresh,
You have encountered a Leaf Beetle in the genus Calligrapha. According to BugGuide: “38 spp. and sspp. in 4 subgenera in our area” and many species look quite similar, so we are reluctant to attempt a species identification.
Letter 17 – Leaf Beetle
Subject: Unknown Beetle
June 3, 2017 6:59 pm
I can’t find a match to the flower leaf eating beetle, can you help.
I think it’s pinkish with three black stripes.
Based on this BugGuide image, we believe your Leaf Beetle might be Calligrapha californica. According to BugGuide: “Host plants are Coreopsis, Bidens and Ambrosia – all composites.” We will be post-dating your submission to go live to our site later in the month when our editorial staff is away on holiday.
Letter 18 – Leaf Beetle
Subject: Fancy mystery beetle
Location: Ashfield, Massachusetts
July 9, 2017 5:25 pm
My son found this boldly patterned beetle that appeared to be brushed with gold dust on a beech sapling that was covered in fat grubs reminiscent of potato beetle larvae that were eating the leaves. I don’t know if the larvae had anything to do with the beetle itself but I thought it might be worth mentioning even though I didn’t get a picture of them. These pictures were taken at the D.A.R. State Forest on June 28, 2017 in Ashfield, Massachusetts. I scoured all my insect field guides and guides to New England wildlife to no avail. I’ve asked amateur nature buffs and no one has been able to identify this little beauty. My brother suggested asking “What’s That Bug.”
Signature: N. Gerlach
Dear N. Gerlach,
This is a Leaf Beetle in the genus Calligrapha, and many species in the genus look very similar. Your individual appears to be Calligrapha rowena based on this BugGuide image. According to BugGuide it feeds: “on Cornus (dogwood).”
Thank you so much! I can’t wait to share this identification with my family.
Letter 19 – Leaf Beetle
Subject: Cute beetle
Geographic location of the bug: Saint Paul, MN
Time: 05:53 PM EDT
I saw this guy and was curious about what he is. Maybe a flea beetle?
How you want your letter signed: Krista
Thanks to this BugGuide image, we have identified your Leaf Beetle as Calligrapha californica. According to BugGuide: “The adult is a dark beige beetle approximately 6 mm long with 3 black stripes on its back” and “Larva feed on beggarticks (Bidens) and possibly other plants.”
Letter 20 – Leaf Beetle
Subject: Wat is this
Geographic location of the bug: Noglaes, Arizona
Time: 03:05 PM EDT
this bug was seen last summer about 10-miles north of Nogales, Arizona
How you want your letter signed: Ben
This is a Leaf Beetle in the genus Calligrapha, and there are many similar looking species in the genus.
Thank you. It was the first time my wife or I had ever seen this particular insect.
Letter 21 – Leaf Beetle
Subject: Rare Type of Ladybug?
Geographic location of the bug: Shenandoah National Park, Virginia, USA
Time: 09:34 PM EDT
Your letter to the bugman: We found this spectacular beetle on Stoney Man Mountain (~3800 ft elevation) in Shenandoah National Park. We thought it might be a rare type of ladybug/ladybird; but we have been unable to find this pattern (with black, red, and shiny gold outlining) in any guide. Can you help us ID this gorgeous beetle?
How you want your letter signed: Adam & Caleb
Dear Adam & Caleb,
This is not a Lady Beetle. It is a Leaf Beetle in the genus Calligrapha, possibly Calligrapha spiraea based on this BugGuide image.
Thank you! That looks like the perfect identification!
Letter 22 – Leaf Beetle
Subject: Beautiful shield (?) bug
Geographic location of the bug: Blue Ridge Mountains, Virginia
Time: 09:55 PM EDT
Your letter to the bugman: My friend found this beautiful bug on his rain gutter downspout this week. It almost looks like a china pattern… can you please help us identify it? I’ve been unable to find any similar pictures online so far. Thank you.
How you want your letter signed: Amy
This is not a Shield Bug. It is a Leaf Beetle in the genus Calligrapha. We suspect it is the wide ranging and considerably variable Common Willow Calligrapha pictured on BugGuide.
Letter 23 – Leaf Beetle
Subject: Small Beetle – Highly Decorated
Geographic location of the bug: Northwest Wisconsin
Time: 11:57 AM EDT
Your letter to the bugman: This beautiful beetle landed on me while walking in a mixed, mature forest near an open area that had been clearcut logged a couple years back. It’s gorgeous markings were very metallic and it happily explored my hand for awhile allowing us a great look. Neither my husband nor I had ever seen one before. Well! Wouldn’t ya know it that a week later at a beach on the Southern shore of Lake Superior there was another, though this individual did not seem as brilliant as the first.
Would love to know what it is and thank you very much for this fabulous site which my sister discovered and recommended.
How you want your letter signed: Critter-Loving Lady
Dear Critter-Loving Lady,
This is a Leaf Beetle in the genus Calligrapha, and there are many similar looking species. Your individual might be Calligrapha rhoda which is picture on BugGuide where it states: “host: Corylus (hazel).”
Letter 24 – Leaf Beetle
Subject: Is this a ladybug?
Geographic location of the bug: San Antonio tx
Time: 12:57 AM EDT
Your letter to the bugman: Hello I’m having trouble finding this bug online.
How you want your letter signed: Erika garza
Letter 25 – Leaf Beetle
Subject: Black and yellow-orange beetle
Geographic location of the bug: Gainesville, Florida, USA
Time: 10:17 PM EDT
Your letter to the bugman: This little beetle was found by my friend, and neither of us can identify it. It’s approximately 5mm long and was found on a bean-like plant.
How you want your letter signed: RobynB.
Dear Robyn B.,
This is a Leaf Beetle in the family Chrysomelidae. We located this image of Lema solani on BugGuide that looks like a match to us, but it feeds on members of the nightshade family, not on beans.
Letter 26 – Leaf Beetle and probably Hemipteran from Indonesia
Location: Ranca Upas, Ciwidey, West Java, Indonesia
January 10, 2013 3:06 pm
I take these picture in a forest 2010, there are two beetles.
The first one with black and beautiful brushed like orange colored, I suspect that this one is a lady beetle but I’m not sure.
and the second one I don’t have a clue what is it.
Hope that you could help.
signature: Mohamad Idham Iskandar
The beetle you believe to be a Lady Beetle is most likely a Flea Beetle, which is a Tribe Alticini within the Leaf Beetle Family Chrysomelidae. Though it is not an exact match, there are certain similarities between your individual and this photo from Encyclopedia of Life. The other insect is a puzzler for us and we have requested assistance from Eric Eaton. While it looks beetle-like, there is something about the eyes that does not seem right. Do you have any additional photos that show the antennae or mouthparts? That might help. Where was this insect found? Was it feeding on a plant? Was it a lone individual? Was it attracted to lights? Please provide any additional information. It almost has us thinking it might be a Hemipteran.
Eric Eaton provides some information
Wow! What a great birthday mystery for me 🙂 Definitely some kind of ‘hopper in the Hemiptera order (and you *can* see one antenna, under the eye on the left side of the image), but it is surely a mimic of a beetle, maybe even a lady beetle. Don’t know where to start….Ooooh, I’ll e-mail this to the wife of the weevil expert, she might know 🙂