Northern Bluet Damselfly – Enallagma cyathigerum
Order Odonata / Suborder Zygoptera / Family Coenagrionidae — narrow-winged damselflies
Live adult damselflies photographed at DuPage County, Illinois, USA
Northern bluet females usually come in two colour forms, either sharing the male’s same blue-and-black coloration (known as homeochromatic morph), or being different, typically brown to olive-coloured (known as heterochromatic morph), and therefore easily distinguishable from the male.
Order Odonata: Dragonflies and Damselflies date back 300 million years, to the Carboniferous Period of the Paleozoic Era. Today, there are about 450 North American species, and 5,000 in all. They have evolved in to highly efficient hunters; their freely moveable heads sport huge compound eyes — in the case of the dragonfly, the eyes nearly cover the entire head — and their sharp biting mouthparts, coupled with their four powerful, independent wings make them extremely agile flyers capable of snatching prey in midair.
These insects cannot fold their wings flat against the body – dragonflies hold them straight out to the sides, damselflies hold then vertically toward the rear. Both families mate in flight and lay their eggs in or close to the water. The mating ritual involves some peculiar acrobatics called a mating “wheel.”
References
- Klaas-Douwe B Dijkstra, Field Guide to the Dragonflies of Britain and Europe (British Wildlife Publishing, 2006).
Tree Encyclopedia / Insects & Spiders
Online since 2002
