Coenagrion is a genus of damselflies in the family Coenagrionidae. Species of Coenagrion occur throughout the Holarctic, including Europe, Asia and North America. They are commonly known as the Eurasian bluets, although several species also occur in North America.
Members of Coenagrion are small to medium-sized damselflies, typically blue and black in colour, and are often associated with ponds, lakes and slow-moving freshwater habitats. The genus includes some of the most widespread and familiar damselflies of the Northern Hemisphere, including Coenagrion puella, Coenagrion pulchellum and Coenagrion hastulatum.
Description
Species of Coenagrion are slender damselflies with narrow wings held closed over the abdomen when at rest. Males are typically bright blue with black markings, while females may be blue, green, brown or pink depending on the species and colour form. Most species inhabit still or slow-flowing freshwater environments, where the larvae develop among submerged vegetation.
Taxonomic history The genus Coenagrion was established by Kirby in 1890 as part of his revision of the damselflies formerly included in the broadly defined genus Agrion. In the same work Kirby recognised the subfamily Coenagrioninae, from which the family name Coenagrionidae is derived.
Coenagrion remains the type genus of Coenagrionidae and is one of the principal genera of the family.
Species The following species are currently placed in Coenagrion:
Biology Thermal adaptation This genus's capacity for phenotypically plastic responses to the surface air temperature is important to species' ranges. These thermal responses will also decide a great deal of these species' responses to climate change. Nilsson-Örtman et al., 2012 find a high degree of thermal adaptation in high latitude populations of Coenagrion. They found similar plasticity even for various sympatric species at the same locations, and despite the highly variable weather at such latitudes.
Etymology The genus name Coenagrion combines the Greek κοινός (koinos, "common") with Agrion, the name of a related genus.
References Lam, Ed. Damselflies of the Northeast, Forest Hill: Biodiversity Press, 2004.
Coenagrion. funet.fi