Emeralds

Corduliidae

Classification

Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Order: Odonata
Suborder: Anisoptera
Family: Corduliidae

Pronunciation

How to pronounce Corduliidae: /kɔrˈduːli.aɪ.iːdeɪ/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Epitheca princeps by the Smithsonian. Used under a CC0 license.

Neocordulia griphus by the Smithsonian. Used under a CC0 license.

Didymops floridensis by the Smithsonian. Used under a CC0 license.

Didymops transversa by the Smithsonian. Used under a CC0 license.

Helocordulia selysii by the Smithsonian. Used under a CC0 license.

Cordulia shurtleffi by the Smithsonian. Used under a CC0 license.

Summary

Corduliidae, known as emeralds or emerald dragonflies, is a family of dragonflies distinguished by their bright emerald metallic green eyes and specific wing patterns. They are medium to large-sized, found in diverse habitats, and include recognizable genera such as Cordulia and Somatochlora.

Physical Characteristics

Usually black or dark brown with areas of metallic green or yellow. Medium to large sized, ranging from 35 to 68 mm long. Characterized by bright emerald metallic green eyes which can sometimes be found on the thorax. Wing patterns consist of dissimilar wing triangles and a foot-shaped anal loop in the hind wing without a distinct toe.

Identification Tips

Individual species can be identified by male tail appendages or female genitalia plates. A field guide with drawings of these features is useful for species identification.

Habitat

Preferred habitats include areas where they can hang rather than perch, often found perching on vegetation or stems at a 45-degree angle.

Distribution

Found nearly worldwide, with around 50 species in various genera in North America alone, and ca. 400 species across the globe in nearly 50 genera and 6 subfamilies.

Diet

Carnivorous; they primarily feed on other insects.

Life Cycle

The larvae are black and hairy-looking, typically found in semi-aquatic environments.

Reproduction

Corduliidae dragonflies often take quantities of their eggs at the tip of their abdomen and then deposit them in mud or water using a sprout-like appendage that extends from their abdomens.

Conservation Status

Some individual species, such as Hine's emerald dragonfly (Somatochlora hineana), are endangered in the United States.

Ecosystem Role

They play a role in controlling insect populations as predators themselves.