United States and Canada

Widespread, large and brightly-colored. One of the most widespread and recognizable species in North America. Often seen feeding in large numbers over open areas. 

Identification: In flight males are easily identified based on their large size, bright green head and thorax and bright blue abdomen. Females are similar, but with reddish abdomens. On males and some females, the base of the abdomen (S1-2, the area under the hindwing) is often strikingly intense blue. 

The face is pale green with a distinct black spot on the top of the frons bordered anteriorly by a blue semicircle giving the impression of a bullseye. The thorax is green with brown only lightly represented on the lateral sutures. The wings are clear with a yellow costa. In males the abdomen is mostly blue, with green on segment 1; greenish-brown or reddish-brown throughout in females. The brown superior caudal appendages in the male are long, about the length of segments 9-10 combined.

Size and Structure: Total length: 68-84 mm; abdomen: 46-60 mm; hindwing: 45-58 mm.

Among the largest dragonflies in North America, combining large size and substantial bulk. Base of abdomen (S1-3) bulky and strongly tapered.

In flight carries its abdomen straight or nearly so (compare Giant Darner). Wingbeats deep with roughly equal lift above and below the shoulder. Flight steady and fast, zooming around ponds at a fairly steady height above the water. Traces long, graceful curves but with sudden acceleration and deceleration. Interacts aggressively but briefly with other Common Green Darners and other species on a nearly continuous basis. 

Perches vertically, hanging from vegetation.

Identification: Male with green eyes; paler below. Face green. Frons green with black spot encircled by green, then an outer blue ring forming a “bull’s eye” pattern. Thorax green. Older individuals with wings turning amber; more so in females. S1 green; S2–6 bright blue laterally and dark brown dorsally (except blue S2) and S7–10 gradually becoming darker, usually going from bluish green to mostly dark. Females usually with S1–2 green and S3–10 reddish brown above with dull green laterally, but some colored similarly to male, with S2–10 black above and blue laterally. Juvenile individuals of both sexes with S3–10 violet laterally.

Similar Species (United States and Canada): Giant Darner (A. walsinghami) is similarly colored, but much larger with a distinctly longer abdomen and relatively shorter thorax; both sexes have lateral stripes interrupted by dark spots on each segment. Female Giant Darners have shorter abdomens (but still longer than the wings); noticeably larger overall than Common Green Darners. Male Giant Darners fly with their long, slender abdomens distinctly curved or drooping downward, a mark which is easily visible in the field; female Giant Darners and male and female Common Green Darners fly with their abdomens straight. 

Both male and female Giant Darner have a relatively much smaller thorax and longer, thinner abdomen than Common Green Darner, so Giant looks less hefty, more long and gangly contributing to the impression in the field of Giant being very large. Some ratios based on this very different structure can be useful for identification of males or females from photos or with binoculars: first, the middle segments of the abdomen are almost as long as the thorax in Giant versus about half as long in Common Green; and second, the abdomen is longer than the hind wings in Giant versus shorter in Common Green. 

The wings of female Giant Darners lacks the amber haze shown by many female Common Green Darners. Also the sides of the abdomen are clearly patterned in both male and female Giant, unlike Common Green which is distinctively plain. Female Giants show a series of pale dots down the side of the abdomen, while Common Green is quite uniform along the sides of the abdomen.

Female Common Green Darners are easily mistaken for Comet (A. longipes) or Blue-spotted Comet Darners (A. concolor), but both have an all-green frons and a pale-spotted abdomen (except mature male Comet Darners have entirely red abdomens).

Amazon Darner (A. amazili) has a triangular spot on the top of the frons (blue outer ring on the frons interrupted in front), distinct white ring basally on S1 and the abdoumen appears spotted.

Great Pondhawk (Erythemis vesiculosa) is smaller, with thinner green-and-black-banded abdomens.

Habitat: Permanent and temporary ponds, lakes, bays and slow-flowing streams with emergent vegetation. Also found hunting where prey is common well away from water. In migration can be found in many habitats. 

Distribution: Found across North America south to Costa Rica. Found in all 50 US states and southern Canada; also West Indies; Guatemala and Belize south to Costa Rica. Recently recorded in England.

Discussion: Females oviposit alone or more often in tandem with male.

A migratory species that is among the earliest species seen in the north, well before it can be found emerging. In the spring, individuals that have emerged in the north will then fly south, some traveling distances as far as from southern Canada to Veracruz, Mexico.

This species is probably one of the most familiar dragonflies in all of North America. It is one of the few North American dragonflies that migrates and is therefore most common in the spring and fall. It is a voracious predator commonly taking wasps, butterflies, mosquitoes, and other dragonflies on the wing. It has even been reported to attack hummingbirds and can be cannibalistic. It is not uncommon to walk through an open field of tall grass in the early morning and have Common Green Darners flying up from their perches low to the ground, an unusual behavior amongst darners. Mating pairs may fall out of the air to the ground or be seen hanging in bushes or trees.

This species is unusual among the darners in the region because females will lay eggs in tandem. Individuals darken considerably in response to cold temperatures but regain their original color upon warming up. There is evidence that its migratory movements are strongly dictated by seasonal warm fronts.

Source: Abbott, J.C. 2006-2010. OdonataCentral: An online resource for the distribution and identification of Odonata. Available at OdonataCentral.

Edited and expanded by David A. Bell (10/01/2015; 07/20/2016).