Beautiful Demoiselle - Calopteryx virgo

Scientific Name: Calopteryx virgo.

English Name: Beautiful Demoiselle.

French Name: Le Caloptéryx vierge.


5 Key Characters:

• the wings of males wide, paddle shaped and more or less entirely dark purplish or greenish blue.
• underneath the last 3 segments on the male's abdomen (known as their 'tail light') orangey or browny red.
• large and robust for a damselfly (45 - 49 mm long).
• male bodies dark metallic blue, female bodies bronzy green.
• female wings broad and distinctly tinted golden brown.

Lookalikes: Banded Demoiselle C. splendens, which has narrower wings. Male C. splendens have yellowish 'tail lights' and only partially dark blue wings. Females are very difficult to distinguish in the field, but C. virgo has more strongly tinted wings and the yellow lateral suture is bayonnet shaped, not an exclamation mark like C. splendens. The lateral suture (on the side of the thorax) can be seen if you have a good photograph. The white pseudopterastigma (near the wing tip) of female C. virgo is closer to the node (in the middle of the leading edge). The distance between the pseudopterastigma and the wingtip should be less than 4 times the distance between the node and the pseudopterastigma. They also prefer different habitats, with C. virgo choosing shadier, faster running streams. Both species have a number of subspecies which are sometimes capable of interbreeding with each other or with the parent species. The local subspecies is C. virgo meridionalis, with males that always have coloured tips to the wings, but the wing bases might be clear for a bit more than 5 mm.

Habitat: Small fairly fast running woodland streams, especially if in steep sided valleys with some sunny spots. The small streams feeding acidic lakes in the Sologne. They avoid large water courses and are highly intolerant of organic pollution. Adults perch on bankside trees and vegetation. Males are territorial and flick their wings to attract females or repulse other males.

Flight Period: April-May-June-July-August-September-October.

Status: Fairly common although they are considerably threatened by modern agricultural practices and 'improvements' to water courses. The complete suppression of bankside trees and bushes and the slashing of vegetation should be avoided if the species is to remain.

Photographed by Loire Valley Nature:
Photographs are numbered from left to right and top to bottom. All photos will enlarge into a new window if you click on them. 1 two male Calopteryx sp. Top right is C. virgo, bottom left is C. splendens - a relatively uncommon example of the two species sharing a habitat, in this case sitting on a Black Alder Alnus glutinosa on the banks of a bief (millstream) in the Aigronne Valley, May. 2 female, Aigronne Valley, May. Note the short bayonnet shaped lateral suture (the yellow mark on the side of the thorax) and the wide golden brown wings. Using Photoshop, the distance between the node and the pseudopterastigma has been calculated as 4 times the distance from the tip to the pseudopterastigma - just on the limit of the ratio acceptable for C. virgo.

A male lands on my boot along the millstream (Fr. bief) in Le Petit Pressigny.

Courtship, female on twig, male flying, above a small stream near Panzoult.