The multicolored Asian lady beetle, a native of Asia, plays an essential role in controlling insect pests.
Known for their distinct appearance, these beetle species showcase a wide range of colors and spot patterns, with some completely spotless.
They can easily be distinguished from others by a pair of white markings behind their head, also known as the “M” shape on their pronotum.
As these beneficial insects are prevalent in various parts of the United States, it’s important to understand their life cycle.
In warm weather, the life cycle of the multicolored Asian lady beetle spans a duration of approximately one month.
During this time, eggs hatch within three to five days and larvae actively feed for around 12-14 days.
After this stage, larvae enter their pupation phase, marking the completion of their development into adult beetles.
These insects feed mainly on aphids and scale insects found dwelling in trees, helping to keep the pests under control.
Understanding the life cycle of the multicolored Asian lady beetle is crucial for maintaining balance within the insect world.
By familiarizing ourselves with these helpful insects, we can appreciate the critical role they play in keeping our environment pest-free.
Asian Lady Beetle Life Cycle
Egg Stage
The egg stage of the Asian Lady Beetle, known scientifically as Harmonia axyridis, is the first step in their life cycle. During this stage:
- Females lay clusters of yellow, oval-shaped eggs.
- Eggs typically hatch in 3-5 days, depending on temperature and humidity.
Larval Stage
The larvae emerge from the eggs and begin their growth and development. At this stage:
- Larvae are black with small orange or yellow markings and have a spiky appearance.
- They feed on aphids and other soft-bodied insects for 12-14 days.
- As they grow, larvae undergo several moltings that help them reach their final size.
Pupal Stage
The transition from larvae to adult occurs during the pupal stage. Some characteristics include:
- Larvae attach themselves to a surface and become immobile.
- They undergo a metamorphosis, lasting 5-6 days, and result in a fully formed adult beetle.
Adult Stage
The adult Asian Lady Beetle is the final stage of the life cycle. Important features include:
- They have a wide range of colors, from orange to red, with black spots varying in number and size.
- Adults feed on harmful insects, such as aphids, making them beneficial for pest control.
- Their life cycle from egg to adult takes around a month, depending on the environment.
Comparison Table
| Stage | Duration | Features |
|---|---|---|
| Egg | 3-5 days | Yellow, oval-shaped eggs |
| Larval | 12-14 days | Black with small orange or yellow markings, spiky appearance |
| Pupal | 5-6 days | Metamorphosis stage, larvae attach to surface and become immobile |
| Adult | Several months | Wide range of colors, varying spot patterns, feeds on harmful insects |
Identification and Varieties
Multicolored Asian Lady Beetle
The Multicolored Asian Lady Beetle (Harmonia axyridis) is native to Asia and has spread to many areas of the United States.
It was introduced as a natural pest controller, preying on aphids and scale insects.
- Size: Small, usually less than 1/4 inch
- Head: Creamy white with a black “W” or “M” shape
- Color: Varies from yellow-orange to deep red
Black Spots
Multicolored Asian Lady Beetles are identifiable by their black spots. However, these spots also vary among individuals.
- Number of spots: 0 to 20
- Shape: Rounded and well-defined
- Location: On the “elytra” or hard wing covers
Physical Features
These beetles exhibit distinct physical features, which include:
- Elytra: Shiny, hard wing covers protect the beetle
- Legs: Short and segmented, used for walking and holding onto surfaces
- Antennae: Used for sensing the environment and locating prey
| Feature | Multicolored Asian Lady Beetle | Other Lady Beetles |
|---|---|---|
| Size | <1/4 inch | Similar, but can vary |
| Head markings | Black “W” or “M” shape | No distinct markings |
| Color | Yellow-orange to deep red | Typically red or orange |
| Black spots | 0-20 | Varies |
| Elytra | Shiny, hard wing covers | Shiny, hard wing covers |
| Legs | Short and segmented | Short and segmented |
| Antennae | Present | Present |
In conclusion, the Multicolored Asian Lady Beetle is a distinct species with unique color patterns and black spot variations.
These features set it apart from other lady beetles and plants, making it easier to identify.
Habitat and Diet
Agricultural Importance
The Asian Lady Beetle, Harmonia axyridis, is native to Asia and has been introduced to the United States as a biological control agent for aphids and scale insects in agriculture.
They have a significant impact on pest populations, especially in crops like soybean due to their voracious consumption of soybean aphids.
Benefits of the Asian Lady Beetle in agriculture:
- Reduces the need for chemical pesticides
- Lowers pest populations
- Increases crop yields
Food Sources in the Garden
Asian Lady Beetles show a preference for certain types of aphids found on ornamental plants and fruit trees, such as plum, peach, and apple trees.
In gardens, they are valuable predators of these pests, helping to ensure healthy plant growth.
Common Asian Lady Beetle prey:
- Aphids
- Scale insects
- Other soft-bodied pests
Example:
Asian Lady Beetles may be seen on a plum tree, actively hunting for aphids and scale insects to consume.
Comparison of Asian Lady Beetles to other beneficial insects:
| Characteristic | Asian Lady Beetles | Lacewings | Praying Mantids |
|---|---|---|---|
| Habitat | Gardens, agricultural fields, orchards | Gardens, agricultural fields | Gardens, agricultural fields |
| Diet | Aphids, scale insects | Aphids, scale insects, other small insects | Large range of insects, including other beneficial insects |
| Agricultural Importance | High | High | Moderate, due to potential consumption of other beneficial insects |
Benefits and Nuisance of Asian Lady Beetles
Pest Control in Gardens and Agriculture
Asian lady beetles are beneficial insects that feed on pests such as aphids and scale insects, reducing the need for chemical pesticides.
They are especially helpful in gardens and agricultural areas, where they can contribute to maintaining a healthy ecosystem.
Some features of their pest control abilities include:
- Efficiently controlling aphid populations
- Multiple generations per year increase their effectiveness
- Predators in both larval and adult stages
Infestations and Issues
However, Asian lady beetles can also be a nuisance, as they tend to infest buildings seeking shelter during winter months.
Their presence can be bothersome for homeowners and other building occupants. Issues related to infestations include:
- Swarms may cause discomfort and annoyance
- Staining on surfaces due to their secreted defensive chemicals
- Allergies or asthmatic reactions in sensitive individuals
Comparison of Asian lady beetles’ benefits and nuisance:
| Benefits | Nuisance |
|---|---|
| Efficient control of aphids and scale insects | Discomfort and annoyance from swarms |
| Multiple generations for persistent control | Staining on surfaces |
| Predator in both larval and adult stages | Potential allergic or asthmatic reactions |
To minimize the nuisance aspect of these insects, homeowners may consider physically removing them by sweeping or vacuuming, as well as sealing gaps and openings in their buildings.
Prevention and Removal
Overwintering Sites
Asian lady beetles tend to overwinter in protected areas like pine trees, cracks, and crevices.
To prevent these beetles from entering your home, identify their overwintering sites and take action. For example:
- Clear away piles of leaves and dead plant materials
- Trim dense vegetation, which can harbor ladybugs
Sealing Gaps and Cracks
Effective prevention involves sealing gaps and cracks in your home’s exterior. You can do this by:
- Caulking around windows and doors
- Installing or repairing screens on windows and vents
- Inspecting and sealing gaps around utility entrances and siding
Pros of sealing gaps and cracks:
- Keeps ladybugs and other pests out
- Improves insulation and energy efficiency
Cons of sealing gaps and cracks:
- Can be time-consuming and tedious
- May require professional assistance for hard-to-reach areas
Vacuuming and Sweeping
If ladybugs have already entered your home, use a vacuum cleaner or sweep them up. Try the following methods:
- Use a vacuum cleaner with a hose attachment to remove ladybugs from walls and ceilings
- Regularly sweep up dead beetles and dispose of them in sealed bags
While vacuuming and sweeping might provide temporary relief, remember that prevention and sealing gaps are long-term solutions.
Insecticides are generally not recommended for ladybug control, as they can stain surfaces and harm beneficial insects.
Vacuuming and sweeping pros:
- Quick and easy method to remove ladybugs
- Doesn’t involve harsh chemicals
Vacuuming and sweeping cons:
- Temporary solution
- Time-consuming to perform regularly
In summary, targeting overwintering sites, sealing gaps and cracks, and vacuuming and sweeping are essential steps in preventing and removing Asian lady beetles from your home.
Common Concerns and Misconceptions
Do They Bite?
Yes, Asian lady beetles can bite, but it is generally mild and harmless. They usually bite when they feel threatened or stressed.
- Their bite is not venomous
- The discomfort is minimal and temporary
Disease Transmission
Asian lady beetles are not known to transmit diseases to humans, pets, or plants.
- They do not carry pathogens
- Their presence is mainly to control pests
Reflex Bleeding
Reflex bleeding is a defense mechanism exhibited by Asian lady beetles. When threatened, they release a small amount of smelly, yellowish fluid from their leg joints.
- This fluid can stain surfaces
- It may cause mild skin irritation but is otherwise harmless
Termites
There is no connection between Asian lady beetles and termites. These insects have different behaviors, habitats, and effects on the environment.
| Asian Lady Beetles | Termites |
|---|---|
| Predators, control pest insects | Wood-destroying pests |
| Beneficial for garden ecosystems | Damaging to human structures |
| Not related to structural damage | Expensive repairs may be needed |
In summary, Asian lady beetles may cause mild discomfort if they bite but do not transmit diseases.
Their reflex bleeding defense mechanism can be visually unpleasant but is not harmful.
They are not related to termites or structural damage and, in fact, have beneficial roles in controlling pest populations.
Alternative Control Methods
Chemical Control Options
Chemical control is one method for managing Asian lady beetles.
However, using insecticides indoors is typically not recommended unless the infestation is severe (USDA ARS). Some chemical options include:
- Pyrethroids: effective against lady beetles, but can be harmful to beneficial insects.
- Carbamates: also effective, but may harm non-target insects and the environment.
Insecticides
When using insecticides, it’s important to select the right product and follow proper application guidelines. Here are some examples:
- Outdoor use: Apply insecticides to exterior walls, windows, and doors to create a barrier against beetles.
- Indoor use: Use only for severe infestations, and follow label instructions to ensure safety.
Pros:
- Effective in reducing beetle populations.
Cons:
- Can harm beneficial insects and the environment.
- Indoor use may pose health risks if not used properly.
Non-Chemical Approaches
Biological control and non-chemical methods can also be effective in managing Asian lady beetle infestations. Some options include:
- Physical removal: Sweeping and vacuuming can help remove beetles from living spaces (USDA ARS).
- Screens and seals: Installing screens on windows and sealing gaps around doors can prevent beetles from entering your home.
- Natural predators: Encouraging native ladybugs and other predators can help control Asian lady beetle populations.
| Chemical Control | Non-Chemical Control | |
|---|---|---|
| Effectiveness | High | Variable |
| Environmental Impact | Can be harmful | Minimal |
| Safety | Use with caution | Generally safe |
Keep in mind that combining different control methods can help achieve better results in managing Asian lady beetle infestations.
Conclusion
To sum up, delving into the Asian lady beetle’s life cycle offers a captivating glimpse into the intricacies of nature.
From egg to adult, this beetle undergoes a remarkable transformation marked by distinct stages and behaviors.
Understanding their life cycle enhances our appreciation for their role in pest control and pollination.
By knowing more about these insects, we can better coexist with them while benefiting from the ecological services they provide to our ecosystems.
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about Asian lady beetles.
Scroll down to have a look at some of them.
Letter 1 – Pupa and Larva of a Multicolored Asian ALady Beetle
Location: Irvine, CA
December 8, 2012 1:03 pm
I recently moved in to a high rise apartment in Irvine, CA, and the other day I started seeing these two bugs.
They don’t seem to move and I’ve only seen them in the one spot outside, I. A wall of a rock bed growing bamboo. What is it???
Signature: Kali
Dear Kali,
This is the pupa of a Lady Beetle. Insects that undergo metamorphosis have two active stages, the larva and the imago or adult, and two inactive stages, the egg and the pupa.
When the weather conditions are right and the proper amount of time has elapsed, this pupa will metamorphose into an adult Lady Beetle or Ladybug.
This appears to be the pupa of a Multicolored Asian Lady Beetle, Harmonia axyridis, an introduced species, and you can compare your image to the photos posted to BugGuide.
Your third photo (the second in our posting) is the larva of the Multicolored Asian Lady Beetle.
Letter 2 – Multicolored Asian Lady Bird Beetle Pupa
Location: Michigan
June 25, 2017 11:32 am
Never seen these before, really curious as to what they are!
Signature: Thankyou
This is the pupa of a Lady Beetle (AKA Ladybug) and normally that would be a good thing as they are important predators that help to control Aphids.
This however is the Pupa of an Invasive Exotic, Multicolored Asian Lady Beetle, a species that is most likely displacing native species as it is so aggressive. Here is a BugGuide image.
Larvae will prey on other Lady Beetle larvae. Multicolored Asian Lady Beetles are reported to invade homes in large numbers to hibernate.
A Facebook Comment from Kiki Gee:
The Asian lady beetle has decimated our indigenous 9 spotted lady beetle. If you ever find one dead or alive, Dr. John Losey at Cornell University would like to know.
I worked with him, and he has an ongoing study trying to increase their population.
Letter 3 – Multicolored Asian Lady Beetle Larva
Location: Long Island, New York
June 2, 2012 1:36 pm
Hey I came across this bug while replacing the boards on my deck, it was just hanging out on a piece of the new lumber. Today (June 2)about a week later I saw it again but this time on one of our plants.
I was hoping that you might be able to help identify it. I did a general internet search trying to use as many descriptors as a could but I was unable to find it. Thanks for your help !!!
Signature: Crystal
Hi Crystal,
This is the larva of a Lady Beetle or Ladybug, and very few people would be able to recognize the larva though the adult is quite familiar to even the youngest child.
We are relatively confident this is the larva of the Multicolored Asian Lady Beetle, a species that has been in the news quite a bit in recent years. This introduced species is believed to be responsible for the drop in populations of our native Lady Beetle species, since it has so readily adapted to living in North America and its numbers are greatly increasing.
This is detrimental to species diversity. Though it is beneficial in the sense that like most other Lady Beetles, both adults and larvae consume great quantities of Aphids and other plant pests, it is highly problematic that it is crowding out and competing for food with our native species.
Additionally, the Multicolored Asian Lady Beetle has gained notoriety in that they often enter homes in great numbers to hibernate, creating quite a nuisance for persnickety homemakers. Much more information on the Multicolored Asian Lady Beetle can be found on BugGuide.
Letter 4 – Larval Multicolored Asian Lady Beetle
Location: Los Angeles, California
March 13, 2012 6:14 pm
Recently, I’ve seen a lot of ladybugs on my rooftop, but it wasn’t until today I noticed these little guys. While I found some information on your site, I’m confused if there is a relationship between what looks like two very different insects.
Moreover, while I don’t mind them, please let me know if there is any reason to curb their spread due to overcrowding. Thank you so much for the informative site!
Signature: WestLABugger
Dear WestLABugger,
Lady Bug is a common name that has no taxonomical relevance since the beloved insects are not bugs, but beetles. Lady Beetle would be a more correct common name. This is the larva of a Lady Beetle.
The plant upon which your photos were taken shows evidence of Aphids, a common food for both adult and larval Lady Beetles. Aphids are significant pests on many cultivated plants and the Lady Beetles help to control their populations naturally without pesticides.
You do not need to worry about overcrowded Lady Beetle larvae since their numbers have a direct relationship to the populations of the Aphids they feed upon.
It appears that your larva is that of the Multicolored Asian Lady Beetle, Harmonia axyridis, an introduced species that has spread throughout North America. The problem with introduced species is that they compete with native species for food and they can displace natives and contribute to the decline of species diversity.
Native Lady Beetle are becoming rarer since the introduction of the Multicolored Asian Lady Beetles. See BugGuide for a matching photo and additional informationon the Multicolored Asian LAdy Beetle.
Daniel:
Thank you so very much for taking the time for the very informative information—I am truly appreciative for the detail and the service you and your team provide.
This is fascinating and I’m relieved to hear I need not doing anything as do love the “Lady Beetle”. I will research the difference between the Multicolored Asian Lady Beetle and the native species for additional knowledge.
I also learned/confirmed from your site that I do in fact have the carpet beetle (not so cute, but so so tiny)
I had to laugh as I somehow always associated them with food, despite the fact that as your site notes, I typically find them near window sills—they never do get out, but I will do my best to escort them outside and do a better vacuum job around the sofa I believe is the culprit.
Thank you again,
“WestLA Bugger”
Letter 5 – Multicolored Asian Lady Beetle Laying Eggs
Location: Maitland, FL
November 30, 2012 1:58 pm
I was in the yard with my camera yesterday and saw a ladybug on some lichen. At first she appeared to be eating it, but that made no sense.
Once I repositioned myself, I could see that she was laying ladybug eggs! How cool! I’m sure it isn’t all that uncommon, but I was excited and wanted to share it with other bug people!
Signature: Brian
Hi Brian,
Your photos are very nice and they are a marvelous addition to our archives. We had hoped that you were lucky enough to have some species of native Lady Beetle laying eggs, but this appears to be the introduced Multicolored Asian Lady Beetle which has become very well established throughout North America.
While they are a beneficial species that feeds on Aphids and other plant pests, it is believed that as their numbers increase, they are crowding out our native species of Lady Beetles which is resulting in decreased species diversity in some areas. You can read more about the Multicolored Asian Lady Beetle on BugGuide.
Letter 6 – Multicolored Asian Lady Beetle Larva
Location: Dallas Texas or Wichita Kansas
April 10, 2013 11:57 am
I live in Dallas Texas. I recently traveled to Kansas. When I got back home, the next day I put on a sweater that i took to Kansas. This later crawled down my arm. I’m not sure if it was from Kansas or Texas. Help!?
Signature: Not a bug guy
immature lady beetle or ladybug
Ed. Note: April 13, 2013
We have a small staff and we haven’t the time to post or even answer all the mail we receive on busy days.
Sometimes we just provide a quick response that is not posted. Sometimes folks like “Not a bug guy” challenge our response, prompting us to take additional action.
Are you sure? It does not look like one at all.
Dear Not a bug guy,
By your own admission, you are “Not a bug guy” and we have been responding to questions about insects on the internet since 1999.
We have always been honest with our readership and we have frequently admitted that we are artists who do not have a background in science, nor more specifically in entomology, but we have learned a thing or two over the years.
We also understand that there is an ever increasing proliferation of sketchy and otherwise unreliable information on the internet and we also know that we are wrong from time to time, but we do make corrections to our postings when errors are brought to our attention in an effort to be as accurate as possible.
With that said, we provided you with a brief response because we do not have the time to answer every query we receive with a lengthy post complete with other internet citations.
Since you seem to be a Doubting Thomas as well as being “Not a bug guy” and since you preferred to request additional feedback from us rather than checking up on the information we provided, we are happy to offer you some clarification to our original response.
Yes, we are sure. We realize that this Lady Beetle Larva does not resemble the adult, but nor does the Luna Moth Caterpillar resemble the ethereal Luna Moth.
Insects undergo metamorphosis, meaning that they often change forms as they grow and mature. If you are still doubting that you submitted a photo of a Lady Beetle Larva, here is a photo from BugGuide of a Multicolored Asian Lady Beetle Larva.
Letter 7 – Multicolored Asian Lady Beetle Larva
Location: Allentown Pennsylvania
June 5, 2016 8:32 am
I have been living in the same house for 3 years and this year, a new bug appeared in my backyard I never seen in my life!
Theres alot and I’m worried they might be poisonous or bite, because of their color and appearance. I have kids so I’m eager to find out what it is and if they are dangerous. Please help!!
Signature: Grace
Dear Grace,
The good news is that this is a Lady Beetle larva, and they are predators that eat other insects and they will not harm your children.
The bad news is that it is a Multicolored Asian Lady Beetle larva, an invasive, exotic species that is crowding out native species of Lady Beetles and threatening their existence.
Furthermore, adult Multicolored Asian Lady Beetles can get very numerous and they enter homes to hibernate, creating a nuisance for homemakers.
Letter 8 – Possibly Multicolored Asian Lady Beetle Eggs
Location: Central Florida
November 13, 2016 11:48 am
Found these eggs attached to the aerial roots of an orchid this morning. Mid Fall and mid morning.
I have both intact and another picture where they had hatched.
Signature: A Constant Florida Gardener
Dear Constant Florida Gardener,
These sure look like the Eggs of a Multicolored Asian Lady Beetle that are posted to BugGuide.
Though they will eat Aphids, we consider the Multicolored Asian Lady Beetle to be an Invasive Exotic species that might be partially responsible for the decline in native Lady Beetle populations. We would not rule out that they are the eggs of a native Lady Beetle.
Thank you so much for the reference and quick response.
Letter 9 – Clime Lab Report: Multicolored Asian Lady Beetle Larvae and Pupae in South Africa
Location: Alberton, Johannesburg, South Africa
February 9, 2017 7:09 am
Good afternoon Bugman,
We have a very big problem with the insects in the below photos, and the problems keeps escalating very quickly. It is a very big concern, as they are busy taking over our whole yard and they leave their sticky residue on everything.
Can you please have a look at the photos and see if you know what this is, and if possible give me some instructions on how we can get rid of them?
The start out like the larvae on the left of the photo , and then become beetles like the one on the right of the photo.
In the bottom photo you can see a whole lot of them together in their various stages of development.
Signature: Filna Heymans
Dear Filna,
It is quite interesting to us that you are concerned about the larvae and pupae of these Lady Beetles, but you have not mentioned the winged adults.
We strongly suspect that these are the early stages of the invasive Multicolored Asian Lady Beetles, Harmonia axyridis, but we had to verify their occurrence in South Africa on iSpot where we discovered the most awesome Clime Lab logo posted by Susana Clusella who is “studying the thermal biology of the alien ladybird Harmonia axyridis (harlequin ladybird, multi-coloured Asian lady beetle) in South Africa and their observations will be useful for determining microclimates.”
The Multicolored Asian Lady Beetle is a threat to native Lady Beetle species in North America because the invasive species is so prolific, and it will prey on native species.
They get quite numerous and they frequently cause homemakers to fret when they enter homes to hibernate in great numbers as the weather begins to cool Though we recognize the threat they make to native species, alas, What’s That Bug? does not provide extermination advice.
Letter 10 – Multicolored Asian Lady Beetle Larva
Location: Southeastern PA
June 7, 2017 5:42 am
this bug/worm/fuzzy looking thing is all over and around my rose of Sharon bushes, but I can’t tell if it is eating what also appears to be tons of tiny aphids, but they are just small lines vs. round – all over the leaves….
not sure if those of the larvae of this, or this is eating those….this bug is less than 3/4″ long and soft bodied vs. beetle-like.
Signature: Eastern PA
This is the larva of a Lady Beetle and it is likely feeding on the Aphids that have infested your Rose of Sharon.
Based on this BugGuide image, we are quite confident that this is the larva of the Multicolored Asian Lady Beetle, Harmonia axyridis, an invasive species that is likely contributing to reduced populations of native Lady Beetles.
Thanks so much. I do not use chemical pesticides or herbicides, but is there anything natural I should/could do to rebalance?
Michele
Letter 11 – Multicolored Asian Lady Beetle Larva
Geographic location of the bug: North Carolina
Date: 11/05/2017
Time: 05:06 PM EDT
I’ve tried to find side-by-side comparisons of the native ladybugs and Asian ladybugs without success. Can you tell me which this one is? I suspect it is Asian.
I have several around my garden, some still in larval form and others pupating. Also, we are having a mild November, but do you know if these will overwinter with me? Thanks a lot!
How you want your letter signed: C. Hall
Dear C. Hall,
In our opinion, this looks like a Multicolored Asian Lady Beetle larva. This species has larger and often more aggressive larvae that out compete, and even feed upon the larvae of native Lady Beetles, which may eventually lead to displacement of native species.
The post Asian Lady Beetle Life Cycle: A Fascinating Journey Revealed appeared first on What's That Bug?.
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