Green Beetle Identification: 11 Shiny Green Beetles

Most green beetles people photograph are one of a short list of metallic species, and size plus where you found it narrows the list quickly.

• Chewing lacy holes in roses, grapes or linden in July or August, 1/3 to 1/2 inch: Japanese beetle.
• Large, 15 to 22 mm, active by day in June in the East, often on ripe fruit: green June beetle.
• Even larger, about 1 1/4 inches, on figs or soft fruit in the Southwest: figeater beetle.
• Running fast on a sunny woodland path in spring, with white spots: six-spotted tiger beetle.
• Small, 8 to 11 mm, iridescent blue-green on dogbane plants: dogbane beetle.
• About 1/2 inch, metallic green with a coppery-red abdomen, on or near ash trees: emerald ash borer.
• At a cow pat, males with a horn: rainbow scarab.
• In Britain: a big green chafer on flowers is usually a rose chafer; a small striped green and purple beetle on rosemary or lavender is a rosemary beetle.

• Japanese beetle: metallic green head and thorax, copper-brown wing covers and five white patches of hair along each side. Adults emerge in late June or early July, feed mainly in July and August, and damage more than 300 plant species, eating the tissue between the veins so leaves look like lace. The grubs are C-shaped, cream-coloured and feed on grass roots (University of Minnesota Extension).
• Green June beetle: 15 to 22 mm long, from dull brown with green stripes to uniform metallic green, with light brown to orange-yellow edges. It flies by day and feeds on ripe or rotting fruit; its range runs from New Brunswick to Georgia and west as far as California. The larvae crawl on their backs and are considered more damaging than the adults (Wikipedia).
• Figeater beetle: about 1 1/4 inches, metallic green, yellowish or reddish depending on the angle. It lives in the southwestern United States and Mexico, eats figs, peaches, grapes, pears and tomatoes, and is often mistaken for the smaller green June beetle (Wikipedia).
• Dogbane beetle: 8 to 11 mm, iridescent blue-green with coppery tones, feeding only on dogbane (Apocynum). Adults emerge in early summer and stay active for six to eight weeks (Wikipedia).

• Six-spotted tiger beetle: 12 to 14 mm, emerald green to blue, usually with three white spots on the rear edge of each wing cover, though some have more, fewer or none (Wikipedia). Ohio State's Joe Boggs describes them as very fast runners and agile flyers that turn to face you on woodland trails from early spring to early or mid summer. Adults and larvae hunt other small arthropods.
• Emerald ash borer: metallic green with a coppery-red abdomen, about 1/2 inch long. It attacks ash trees and leaves D-shaped exit holes in the bark. First detected in North America in 2002 in southeast Michigan, it has been found in 38 states and Washington, D.C. (USDA APHIS).
• Rainbow scarab: an iridescent dung beetle 11 to 22 mm long; males carry a large horn on the head. It feeds on dung, mainly from pasture animals, and occurs from Florida and New England west to Arizona and Wyoming (Wikipedia).

The Wildlife Trusts list four green beetles that people commonly meet:

• Rose chafer: a large, iridescent green beetle with short creamy-white streaks on the wing cases, sometimes coppery or golden; May to October in woodland, parks and gardens in southern England and Wales.
• Green tiger beetle: up to 15 mm, metallic green with yellowish spots, purple-bronze legs and large eyes; April to September on bare sandy ground.
• Swollen-thighed beetle: slender and metallic green with a gap between the wing cases; April to September in meadows.
• Rosemary beetle: small and shiny with metallic green and purplish-red stripes; on rosemary, lavender and thyme all year, most often in May and June.

These three are confused more than any other green beetles.

• Size: Japanese beetle 1/3 to 1/2 inch; green June beetle 15 to 22 mm (about 0.6 to 0.9 inch); figeater about 1 1/4 inches (University of Minnesota Extension; Wikipedia).
• Colour pattern: only the Japanese beetle has copper-brown wing covers and white hair tufts along the sides.
• Where: Japanese and green June beetles are eastern; the figeater is southwestern (Wikipedia).
• What it eats: Japanese beetles skeletonize leaves; green June beetles and figeaters go for ripe fruit (University of Minnesota Extension; Wikipedia).

To people, the beetles on this page are not described as dangerous, with two cautions. Tiger beetles can bite if handled (Wikipedia). The dogbane beetle stores cardenolides from its host plant, compounds that can cause cardiac arrest if eaten (Wikipedia), so do not let children or pets eat one; if that happens, call a doctor, a vet or Poison Help (1-800-222-1222 in the US).

To plants and trees, several are pests. Japanese beetles feed on more than 300 plant species; University of Minnesota Extension recommends knocking them into a bucket of soapy water and advises against traps, because more beetles fly toward traps than are caught. Emerald ash borer attacks ash trees; APHIS asks people to buy local or certified heat-treated firewood and to report suspected infestations. Tiger beetles are predators of other insects.

In practical terms, it tells you about the season and what is growing nearby. A Japanese beetle in July or August means a host plant such as rose, grape or linden is close (University of Minnesota Extension). A green June beetle in early summer means ripe fruit is nearby, and its grubs may be in the soil (Wikipedia). A dogbane beetle means dogbane is growing there. A metallic green beetle about 1/2 inch long on an ash tree is the one worth reporting to your state agriculture department or APHIS.

Metallic beetles change colour with the angle of light, so take two photos from slightly different angles, one from above and one from the side, with a coin or ruler for scale. Capture the sides of the abdomen (Japanese beetle hair tufts), the rear edge of the wing covers (tiger beetle spots) and the host plant. Photograph the beetle and InsectLens names it. For more green insects that are not beetles, see green bug identification; for beetles in general, see beetles.

Research and drafting for this page used AI assistance. Every figure, date and quotation was then checked line by line against the sources listed at the bottom of the page, each of which was opened while writing. Nothing here is a diagnosis. If a bite, sting or contact with an insect is followed by trouble breathing, swelling of the face or throat, spreading redness, fever or any symptom that worries you, get medical care; in the United States Poison Help (1-800-222-1222) is free and open 24 hours a day.