Originally published 08/07/2015.
The Four-spotted Chaser, Libellula quadrimaculata, is a magnificent dragonfly to watch! They live up to their name by often chasing away intruders from their territories and will often stop to hover nearby, giving you the chance to get up close to a dragonfly in flight- a fairly rare treat.
The four-spotted chaser occupies a variety of standing waters, including bogs, ponds and ditches. It seems to favour acidic waters and does extremely well in bogs and heathland pools. It can also be found in lakes, streams and canals. It is common and widespread throughout the UK.
Both males and females look extremely similar in this species. Both sexes have a dark yellow/light brown abdomen, with yellow on the edges of most segments and the tip of their abdomen is black. They also have a brown thorax and brown eyes.
The wings are the defining feature of this species and are the easiest means of identifying this dragonfly whilst it is perched. Each wing has a black wing spot (pterostigma) but also has a dark spot or patch at the wing node (roughly halfway down the wing). This dark spot at the node gives each wing the appearance of having two spots, totalling to the appearance of four spots on each side of the dragonfly, hence the name.
Each forewing has yellowing at the wing base and each hindwing has dark patches at the wing base. There is a fairly common form of this species, praenubila, in which the wings have additional dark smudges near the wings tips. This is an obvious marking, but the four ‘spots’ on each side are still obvious for the identification.
Males are very territorial and will often patrol their territories, chasing away intruding dragonflies. It is common to see Four-spotted Chasers chasing other males and often you will hear a ‘crackle’ from the males as the collide with one another. During territorial patrols, males will often stop and hover for long time periods, returning to a favoured perch once they are satisfied their territory is safe.
The Broad-bodied Chaser, Libellula depressa, and the Scarce Chaser, Libellula fulva, both look similar to the Four-spotted Chaser. The easiest way to tell these species apart is to look for the four black wing markings.
The broad-bodied chaser can also be told apart as it has a much thicker abdomen than the other chasers. It also has dark colouration at both the forewing base and hindwing base, as opposed to the Four-spotted that only has dark colouration at the hindwing base.
The Scarce Chaser male can be told apart as it develops pruinescence, giving it a blue colouration and making it noticeably different from the dark yellow-brown of the Four-spotted. The Scarce Chaser female can be told apart as it has a dark brown/black stripe down the middle of the abdomen, which the Four-spotted Chaser does not have.
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