Four-spotted chaser (Libellula quadrimaculata)
| French: | Libellule Quadrimaculée |
|---|
| Kingdom | Animalia |
|---|---|
| Phylum | Arthropoda |
| Class | Insecta |
| Order | Odonata |
| Family | Libellulidae |
| Genus | Libellula |
| Size | Wingspan: 75 mm Average body length: 43 mm |
The four-spotted chaser is classified as Least Concern (LC) on the IUCN Red List (1).
The four-spotted chaser (Libellula quadrimaculata) gets its name form the four dark spots present at the midpoint of the front of each of its four wings. Unusually for this family, males and females are much alike in appearance; the basic colouration is dark honey-brown, with a paler scalloped edge to both sides of the abdomen. The tip of the abdomen is black. Some members of the family Libellula tend to have fatter abdomens than other Odonata species. Several other male species in the family have noticeably blue upper sides to the abdomen, especially the broad-bodied chaser Libellula depressa.
Four-spotted chasers are found throughout the British Isles, including the Scottish Islands and Ireland. Their range covers much of Europe and Northern Asia and extends into North America.
The four-spotted chaser can usually be found around most water bodies, including pools, rivers and upland lakes and lochs.
Male four-spotted chasers are active insects and spend long periods of time hawking over the water and surrounding vegetation, both hunting for other insects and marking out their territories. They appear from late May until August, and must mate and reproduce during this short season. Mating takes place on the wing and the females then hover over the water surface, dropping her eggs which sink down to adhere to submerged vegetation.
As with other Odonata species, the larvae of the four-spotted chaser live for about two years amongst the vegetation and muddy debris at the bottom of their pond. They are voracious predators of other water creatures. When they have grown to a large enough size they climb up the stems of emergent vegetation before completing their transformation into adults.
The four-spotted chaser appears to be common and widespread throughout the UK and, provided that clean water and marginal vegetation are available, there appear to be no special threats to its survival.
There are currently no conservation projects for the four-spotted chaser in the UK.
For more on British dragonflies:
-
The British Dragonfly Society:
http://www.dragonflysoc.org.uk/
Information supplied by English Nature.
http://www.english-nature.org.uk
- Abdomen: in arthropods (crustaceans, insects and arachnids) the abdomen is the hind region of the body, which is usually segmented to a degree (but not visibly in most spiders). In crustacea (e.g. crabs) some of the limbs attach to the abdomen; in insects the limbs are attached to the thorax (the part of the body nearest to the head) and not the abdomen. In vertebrates the abdomen is the part of the body that contains the internal organs (except the heart and lungs).
- Larvae: stage in an animal’s lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.
- Territory: an area occupied and defended by an animal, a pair of animals or a colony.
-
IUCN Red List (April, 2011)
http://www.iucnredlist.org/