Coenagrion johanssoni
Coenagrion johanssoni Wallengren, 1894
Local names: Arctic bluet, Nordische Azurjungfer, Noordse waterjuffer, Myrflickslända
Species Information
Description
One of the smallest species of the genus Coenagrion, with a short and thin abdomen. The males are blue with black markings. Postocular spots are pear-shaped. The males have dorsally on the second abdominal segment (S2) a marking in the shape of a U. In some individuals the the latter marking is connected to a band at the rear margin of the segment by a black line, thus forming a sort of Y, somewhat as on C. pulchellum. On the sides of the S2 marking there is a backwards pointing "spike". It can be likened to a resting cat where the spike would make the front legs. The males have the dorsal parts of S9 and S10 light blue.
The females have the dorsal part of the abdomen completely black, except for S9 and S10 that are blue. Females coloured parts vary in colour from blue to green and to almost chocolate brown. Both sexes have two black lines , much like prongs, on the sides of the abdomen. These markings only also appear on C. hylas and gives that species a darker general impression, but C. johanssoni is much smaller in size than C. hylas.
The pterostigma is rather short and black in colour in both sexes. Legs are lightly coloured with black lines and appear weaker than other similar species. As always with Coenagrionidae, the shape of the pronotum is characteristic for the species.
Size
Habitat
In Europe, this boreal species is found in peat bogs, transition mires, fens, ponds and lakes bordered with Sphagnum peat moss rafts. Suitable habitats are often in or nearby forests. C. johanssoni is mostly found in lowlands but has been recorded up to 1 000 m in Norway and Sweden.
Distribution
Coenagrion johanssoni has the northernmost distribution of all European damselfly species, almost completely overlapping the taiga forest. More rarely small populations are found in the tundra and in the transition area between the taiga and the tundra. The species is widespread moderately common in most of Fennoscandia, although it is rare in the mountains of Norway and Sweden. It is reasonably widespread, although decreasing from the north to the south, in the Baltic states and Belarus. The species is probably common and widespread in the boreal parts of the European Russia, although many of the records from this area needs confirmation. It is well established in southern Urals.
Flight Period
May to August
Behavior
This species stays low in the vegetation, much like C. armatum and Nehalenna speciosa. But being overall more common than the both of them it is more easy to find. It can also be found flying along shores and during mating pairs can be spotted a bit away from the water, for example in nearby glades.
Conservation Status
Similar Species
Coenagrion lunulatum
External Links
Genus: Coenagrion
Coenagrion is a genus of damselflies in the family Coenagrionidae, commonly called the Eurasian Bluets (although three species are found in North America). Species of Coenagrion are generally medium-sized, brightly coloured damselflies.
Identification
Males are small blue damselflies with black markings. The blue areas may be partly greenish or whitish. Females have more extensive black markings, and are more often green or brownish. A damselfly with plain pterostigmas, with roundish postocular spots, with antehumeral stripes narrower than the black line below it, and with two short black lines on the thorax sides, will in most cases belong to Coenagrion.
Separation from other genera
Enallagma normally have antehumeral stripes wider than the black line below them and just one short black line on the thorax side. Ischnura males have bi-coloured pterostigma. Enallagma and Ischnura females have a vulvar spine. Erythromma species are darker, with reduced or no postocular spots, and males have red or all-blue eyes, whereas eyes of Coenagrion are blue with dark caps. The blue Erythromma lindenii is very similar, but differs in many details, like wider antehumeral stripes, an all-black upperside to S2 and a shorter 'tail-light' positioned further at the tip of the abdomen.
Behaviour
Males typically fly low among or along riparian vegetation. They rarely venture far from water. MAles and females in tandems often oviposit in concentrations on floating vegetation. The male often holds a conspicuous upright posture when in tandem with the female.
Family: Coenagrionidae
The insect family Coenagrionidae is placed in the order Odonata and the suborder Zygoptera. The Zygoptera are the damselflies, which although less known than the dragonflies, are no less common. More than 1,300 species are in this family, making it the largest damselfly family. The family Coenagrionidae has six subfamilies: Agriocnemidinae, Argiinae, Coenagrioninae, Ischnurinae, Leptobasinae, and Pseudagrioninae.
This family is referred to as the narrow-winged damselflies or the pond damselflies. The Coenagrionidae enjoy a worldwide distribution, and are among the most common of damselfly families. This family has the smallest of damselfly species. More than 110 genera of the family Coenagrionidae are currently accepted.
The family was named by William Forsell Kirby in 1890. The name may be derived from Greek coen meaning shared or common and agrio meaning fields or wild.