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Beautiful demoiselle

 

 

The photos of nature loving photographers mostly catch the colourful male demoiselle specimens. There are no definite facts but the colourful males seem to be proportionally more numerous.

 

We see the beautiful demoiselles mostly near clean watercourses with sand or gravel bottoms; but they are not particularly finicky about their habitat, and some individuals can be encountered quite far away from rivers and creeks.

 

The demoiselles’ body length is less than five centimetres and the length of the hind wing is over one centimetre less; thus the relationship between body and wing lengths is clear. The male’s body colour is an electric blue that light may change into emerald green. The undersides of the tip segments of teh abdomen are reddish brown. The wings have a metallic gleam and are pigmented a dark blue, with a metallic lustre. The wing tips can be translucent to light.

 

Beuatiful demoiselle

 

The body of the female demoiselle is greenish, or a  bronze-tinted brown may be added, and on the last tip segments is a yellowish stripe. The colour of the semi-transparent wings is brownish. The wing is decorated with an apparent “dot”, a pseudo-pterostigma, that is located some distance from the wing tip. Arne’s photos show the characteristics nicely.

 

The males defend their territories against intruders of the same sex. If the intruder does not retreat after the first attack, such an attack game, at a distance of some twenty centimetres apart from each other, can sometimes last up to an hour.

 

When a female arrives into a male’s territory she must show her willingness to mate or leave. After mating the male often guides the female to a suitable egg-laying spot, staying himself to stand guard. Eggs are laid on aquatic plants, also under water,  and they can be up to 300. After a few weeks long-legged larvae, about four millimetres long, hatch. They will have a life of two years in the water.

 

The lifetime of the imago is about a month and a half, and the flight time is mostly in mornings. As with the other Odonatae - dragonflies and damselflies - the imagos are predators, hunting insects by stalking from a selected tree, shrub or a taller plant.

 

The flight image of the demoiselle imagos reminds of the flittering of butterflies, somehow with slower wing beats than those of the other relatives, the pond damselflies (Coenagrionidae)  and spreadwings (Lestidae), whose wings are transparent.

 

The males of banded demoiselle (C. splendens) have partly blue wings but we meet them much more rarely.

 

Beautiful demoiselles