Look at the white area just behind the head. A multicolored Asian lady beetle almost always has a black mark there shaped like an M (or a W, depending on which way you look). Classic ladybugs such as the seven-spotted lady beetle have a mostly black area behind the head with a small white patch on each side, and the convergent lady beetle has two white lines that angle toward each other. Asian lady beetles also vary far more in color, from pale tan to orange to red, with anywhere from no spots to many.
If you have dozens or hundreds of “ladybugs” gathering on a sunny wall in October, they’re almost certainly Asian lady beetles.
Side-by-side comparison #
| Feature | Multicolored Asian lady beetle | Seven-spotted lady beetle | Convergent lady beetle |
|---|---|---|---|
| Scientific name | Harmonia axyridis | Coccinella septempunctata | Hippodamia convergens |
| Color | Tan, yellow, orange or red | Red to orange-red | Orange to red |
| Spots | None to many, variable | Exactly seven black spots | Usually up to 13, sometimes fewer |
| Behind the head | White with a black M or W mark | Black with a white patch on each side | Black with two white lines angling together, white edges |
| Size | About 1/4 inch | Similar | Slightly smaller |
| Shape | Oval, a bit more elongated | Round and domed | Oval |
| Invades homes in swarms? | Yes, in fall | Rarely | Rarely |
| Origin in North America | Introduced from Asia | Introduced from Eurasia | Native |
The Asian lady beetle #
The University of Kentucky describes the multicolored Asian lady beetle as about a quarter inch long and oval, with colors from tan to red and a distinctive M- or W-shaped marking on the whitish area behind the head. Individuals with many spots tend to be female, and those with few or no spots tend to be male. The species is native to Asia and has spread across much of the US since the 1980s.
In the garden, Asian lady beetles are useful. Adults and larvae eat large numbers of aphids and other soft-bodied pests. The trouble starts in fall.
Why they swarm your house #
Asian lady beetles spend the winter in sheltered crevices. In their native range those are cliffs and rock outcrops. Here, sunny, light-colored walls of houses do the job. Kentucky’s entomologists report that swarms fly to buildings from September through November, with most movement in October, typically on sunny afternoons after a spell of cooler weather. They squeeze into gaps around windows, siding, soffits and attic vents, and on warm winter days some wander into living spaces.
They don’t breed, eat or damage anything indoors. They’re a nuisance, but a persistent one.
Do they bite? #
Sometimes. Kentucky’s fact sheet says the bite feels like a pinprick and is seldom serious. It usually happens when a beetle lands on skin, especially when they’re hungry and restless indoors.
The smell and the stains #
When disturbed or crushed, Asian lady beetles release a yellowish fluid from their leg joints that has an acrid smell and can stain walls, curtains and fabrics. That’s why crushing them is a bad idea.
The seven-spotted lady beetle #
The ladybug from children’s books is usually the seven-spotted lady beetle. The Missouri Department of Conservation describes it as reddish with black spots, a shiny, round, domed body, and a white spot on either side of the head. It’s native to Eurasia, the most common lady beetle in Europe, and was introduced to North America in the mid-1900s to help control aphids.
Seven spots in a 3-1-3 arrangement, plus the black-and-white head pattern, make it one of the easier lady beetles to pin down.
Native ladybugs #
North America has hundreds of native lady beetle species. The convergent lady beetle is one of the most familiar and is often sold for release in gardens. Others include the two-spotted, fourteen-spotted and twice-stabbed lady beetles. Several native species have declined as introduced ones spread, which is one reason researchers ask the public to report lady beetle sightings.
Native lady beetles overwinter outdoors in leaf litter or in clusters on hilltops, not in houses, so they rarely turn up indoors in large numbers.
How to keep Asian lady beetles out #
The University of Kentucky’s advice centers on sealing up before fall and gentle removal once they’re in:
- Seal gaps in late summer. Caulk cracks around windows, doors, siding, utility pipes and fascia boards. Repair torn screens and add screening to attic and soffit vents.
- Vacuum, don’t crush. Use a vacuum to collect beetles indoors. A knee-high stocking stuffed into the vacuum hose and held with a rubber band lets you empty them outside without them getting into the bag.
- Use light traps in attics or dark rooms if large numbers are coming in.
- Skip indoor insecticide sprays. Dead beetles in wall voids can attract carpet beetles, and sprays don’t stop new ones from arriving.
A professional exterior treatment in early fall can reduce numbers in bad years, but sealing gaps does more over time. The same steps also keep out stink bugs and boxelder bugs, covered in stink bug season.
Identify your lady beetle from a photo #
Photograph the beetle from above, with the head and the area behind it sharp. That’s where the M mark, the white side patches or the converging lines appear. A second shot at a slight angle helps if the light is reflecting off the shiny shell.
Insect Identity includes the Asian lady beetle, seven-spotted ladybug, convergent lady beetle, fourteen-spotted lady beetle and twenty-two-spot ladybird among its 224 species. It gives a best match with a confidence score and four runners-up, which is useful here because these beetles are so similar: if the top two are close, look again at the marking behind the head. It runs offline, so you can check a beetle on the wall without any signal. For garden helpers in general, see beneficial insects for the garden, and for other mystery bugs indoors, what is this bug in my house.
Frequently asked questions #
Are Asian lady beetles harmful? #
Not seriously. They can give a pinprick bite, release a smelly yellow fluid that stains, and gather in annoying numbers, but they don’t damage homes, eat food or fabric, or spread disease. Outdoors they’re helpful aphid predators.
Why do Asian lady beetles bite but ladybugs don’t? #
Any lady beetle can pinch skin with its jaws, but Asian lady beetles are the ones that end up indoors in large numbers, hungry and dried out over winter. That makes them far more likely to land on people and nip.
Are orange ladybugs poisonous? #
They’re not poisonous to touch. Orange lady beetles are often Asian lady beetles, which release a bad-tasting, bad-smelling fluid when handled or crushed. Wash your hands after handling them and keep them out of pets’ mouths.
How do I get rid of Asian lady beetles in my house? #
Vacuum them up gently and release or dispose of them outside, and seal cracks and gaps before the next fall. Crushing them causes stains, and indoor sprays don’t stop new beetles from coming in.