Green Bugs: 10 Common Types to Know
Found a green bug? This guide lists 10 common bugs that are green in color, ordered from most to least risky, with the one feature that identifies each.
Quick list
How to narrow it down
Narrow it down with three quick checks. Count the legs: insects have six, spiders and ticks have eight, and centipedes and millipedes have many more. Check for wings, even folded ones. Then compare size against a coin: a US penny is 19 mm across. Our bug identifier tool does this filtering for you.
The 10 bugs
Aphid
AphidAphidoidea superfamilyA tiny, soft, pear-shaped insect that clusters on new shoots and leaf undersides to suck sap. Aphids reproduce quickly and leave sticky honeydew that attracts ants.
Tell-tale sign: Pear-shaped, soft body, often green or black. Risk: Aphids don't bite people; heavy colonies curl leaves and spread plant viruses.
Blow Fly
Blow FlyLucilia sericataA shiny, metallic green or blue fly that lays eggs on dead animals, meat and garbage. A sudden swarm indoors often signals a dead mouse or bird in a wall or attic.
Tell-tale sign: Metallic green, blue or bronze body. Risk: Blow flies don't bite but can carry bacteria from rotting material.
Differential Grasshopper
Differential GrasshopperMelanoplus differentialisA large, olive-yellow grasshopper with black chevron marks on its hind legs. It feeds on crops, vegetables and weeds across the central US.
Tell-tale sign: Yellowish-olive body. Risk: Grasshoppers can nip if handled but are harmless; large outbreaks damage crops.
Emerald Ash Borer
Emerald Ash BorerAgrilus planipennisA slim, bullet-shaped, metallic green beetle whose larvae tunnel beneath ash tree bark. It has killed hundreds of millions of ash trees across North America.
Tell-tale sign: Bright metallic emerald green body. Risk: Emerald ash borers are harmless to people but lethal to untreated ash trees.
Japanese Beetle
Japanese BeetlePopillia japonicaA metallic green beetle with copper-brown wing covers that skeletonizes the leaves of roses, grapes, linden and hundreds of other plants. Its white grubs feed on grass roots in lawns.
Tell-tale sign: Metallic green head and thorax with coppery wing covers. Risk: Japanese beetles do not bite or sting people; the harm is to plants and turf.
Tomato Hornworm
Tomato HornwormManduca quinquemaculataA huge, bright green caterpillar with white V-shaped marks and a horn on its rear end. It can strip tomato, pepper and eggplant leaves overnight and later becomes a hawk moth.
Tell-tale sign: Plump green caterpillar up to four inches long. Risk: The horn is harmless; hornworms don't sting or bite.
Common Green Darner
Common Green DarnerAnax juniusA large dragonfly with a bright green thorax and, in males, a blue abdomen. It patrols ponds and fields catching mosquitoes and other flying insects.
Tell-tale sign: Green thorax with a bull's-eye mark on the face. Risk: Dragonflies can't sting and almost never bite people.
Green Lacewing
Green LacewingChrysoperla carneaA delicate, pale green insect with golden eyes and clear, net-veined wings. Its larvae, called aphid lions, devour aphids, mites and other soft-bodied pests.
Tell-tale sign: Lacy, transparent wings folded roof-like over the body. Risk: Lacewings are harmless beneficial insects; larvae can occasionally nip skin.
Luna Moth
Luna MothActias lunaA large, pale lime-green moth with long, sweeping tails on its hind wings. Adults don't eat and live only about a week to mate.
Tell-tale sign: Pale green wings with long, curved hindwing tails. Risk: Luna moths are completely harmless; adults have no functional mouthparts.
Praying Mantis
Praying MantisTenodera sinensisA large, long-bodied predator that waits motionless with its spiny front legs folded as if praying. It catches insects of all kinds, including beneficial ones.
Tell-tale sign: Triangular head that swivels to look over its shoulder. Risk: Mantises are harmless to people, though a large one may pinch if handled.
Which ones should you worry about?
0 of the 10 bugs in this guide can bite or sting. None of them are considered medically significant. The rest are harmless or simply a nuisance.
Comparison at a glance
| Aphid | Blow Fly | Differential Grasshopper | |
|---|---|---|---|
| Group | True Bugs | Flies & Mosquitoes | Other Insects |
| Scientific name | Aphidoidea superfamily | Lucilia sericata | Melanoplus differentialis |
| Size | 1–3 mm | 8–12 mm | 28–50 mm |
| Colors | Green, Black, White and Yellow | Green, Blue and Metallic | Yellow, Brown and Green |
| Legs | 6 legs | 6 legs | 6 legs |
| Wings | No | Yes | Yes |
| Bites or stings | No | No | No |
| Risk | Nuisance | Nuisance | Nuisance |
| Key feature | Pear-shaped, soft body, often green or black | Metallic green, blue or bronze body | Yellowish-olive body |
Frequently asked questions
What is the most common one?
Among the bugs in this guide, the aphid and blow fly are the ones people ask about most.
Which of these are dangerous?
None of them are medically significant, though some can bite or sting.
How can I identify a bug I found?
Use the free bug identifier tool: choose the number of legs, wings, main color, size and where you found it, and it will list the closest matches.