Northern damselfly

Description

Coenagrion hastulatum, the northern damselfly or spearhead bluet, is a damselfly in the family Coenagrionidae. The species is widespread and common in northern Eurasia but is restricted to elevated or bog-like sites towards the west and south. In Britain, it is confined to a few small lochans in Scotland. C. hastulatum is 31–33 millimetres (1.2–1.3 in) long. The specific part of the scientific name, hastulatum, from the Latin hastula (small spear) is because of the distinctive markings on the second segment of the abdomen that resembles a spear. Coenagrion is a genus of damselflies in the family Coenagrionidae, commonly called the Eurasian Bluets (although three species are found in North America: Coenagrion angulatum, Coenagrion interrogatum, and Coenagrion resolutum). Species of Coenagrion are generally medium-sized, brightly coloured damselflies. 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.