The bean plataspid, better known in the U.S. as the kudzu bug, is a small, round bug from Asia, about 1/8–1/4 in (3.5–6 mm) long, that feeds on kudzu, soybeans, and other legumes. It arrived in the U.S. in 2009 and spread quickly through the Southeast, where it damages soybeans. It is also a nuisance in fall, when it gathers in large numbers on light-colored houses.
Appearance
- Appearance
- Adults are about 1/8–1/4 in (3.5–6 mm) long, rounded to slightly oblong, and light brown to olive green with fine dark pits. A large shield on the back covers the wings and most of the abdomen, so it looks a bit like a small beetle.
Look-alikes
Typical stink bugs have a triangular shield in the middle of the back, while the kudzu bug's shield is broad and squared off at the back and covers almost the whole body.
Why they get mixed upBoth are smelly plant-feeding bugs, and the kudzu bug is sometimes called the globular stink bug.
Where it lives
- Typical habitats
- Kudzu patches
- Soybean fields
- Around homes
- Range
- Native to Asia. In the U.S., it was first found in 9 counties of northeast Georgia in 2009 and has since been reported in at least 18 states across the Southeast, including the Carolinas, Alabama, Florida, Tennessee, Virginia, Maryland, and Mississippi, with sightings in Texas by 2017.
- When to see it
In the US
Active Apr–Oct
Behavior
- Diet
- Adults and nymphs suck sap from the stems and leaves of kudzu, soybeans, and other legumes such as beans and wisteria.
- Activity
- In the U.S., bugs move onto kudzu and wisteria in spring, shift into soybeans in July and August, and stay active until about October. They are drawn to white and other light-colored surfaces.
- Overwintering
- Adults spend winter under bark, in leaf litter, or in sheltered spots on buildings, sometimes slipping into walls and attics. In warm areas they may stay active year-round.
Life cycle
- Reproduction
- Females lay egg masses along with small dark capsules full of symbiotic gut bacteria. Newly hatched nymphs eat the capsules to pick up the bacteria; without them, nymphs grow slowly and many die.
- Larva
- Nymphs pass through five stages. They are hairy and pale orange, olive green, or light brown.
Cautions
- Cautions
- When disturbed or crushed, it releases a foul-smelling liquid that can cause a burning feeling or a red welt on skin and leaves yellowish stains on fabric, wood, and siding.
Name and classification
- About the name
- U.S. agencies and universities call this bug Megacopta cribraria. In Japan, the very similar bug of the main islands is treated as a separate species, Megacopta punctatissima, and some researchers think the two are just local forms of one species. Genetic work shows the U.S. population is closest to the Kyushu populations of M. punctatissima.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
More species to explore
Record what you meet and build your own collection
Your photos are kept with their date and place, and you can fill regional albums one species at a time.