There are approximately 3,600 known species of dragonfly in the world. In the British Isles there are 27 species of dragonfly. Below are just a few examples of Dragonfly that live on our planet.
The Emperor dragonfly (Anax imperator) has the largest wingspan of any Dragonfly in the British Isles which measures 10.5 centimetres long. The Emperor dragonfly is a large and powerful species of European hawker dragonfly of the family ‘Aeshnidae’.
The Emperor dragonfly has a body length of up to 8 centimetres. (The Golden-ringed dragonfly (Cordulegaster boltonii) has the longest body length of all British dragonflies measuring up to 8.6 centimetres). The male Emperor dragonfly has a brilliant sky blue coloured abdomen and an apple green thorax and the female has a green thorax and abdomen. Both have a black stripe down the back of the body. The Emperor dragonfly is found in southern England and Wales, around large ponds, canals, gravel pits, slow rivers and lakes during the summer months. It is not found in Scotland or Ireland.
Emperor dragonflies frequently fly high up into the sky in search of prey, which includes Butterflies to Four-Spotted Chasers. Small prey is eaten on the wing (while in flight). The females lay their eggs on plants such as pondweed and always lay them alone.
The Common Whitetail Dragonfly or Long-tailed Skimmer (Libellula lydia) is a common dragonfly across much of North America. The Common Whitetail Dragonfly has a striking and unusual appearance. The males chunky white body measures about 5 centimetres long.
The Common Whitetail Dragonfly has brownish-black bands on its otherwise translucent wings, giving it a checkered look. Females have a brown body and a different pattern of wing spots, closely resembling that of a female Twelve Spotted Skimmer (Libellula pulchella), but can be distinguished by their smaller size, shorter bodies and white zigzag abdominal stripes.
The Common Whitetail can be seen hawking for mosquitoes and other small flying insects over ponds, marshes and slow-moving rivers in most regions except the higher mountain regions. Common Whitetails often rest on objects near the water and sometimes on the ground. Males are territorial, holding a 10 to 30 metre stretch of the waters edge and patrol it to drive off other males.
The nymphs of the Common Whitetail Dragonfly are dark green or brown, but are usually found covered in algae. They feed on aquatic invertebrates such as mayfly larvae and small crayfish and also on small aquatic vertebrates such as tadpoles and small fish.
The Southern Hawker Dragonfly (Aeshna cyanea), is also known as the Blue Darner in the Western Hemisphere. It is one of the hawker dragonflies from the family Aeshnidae. The Southern Hawker Dragonflies are widespread throughout Europe.
The Southern Hawker Dragonfly is a large dragonfly and has a long body measuring 70 millimetres in length. It has green markings on a black body and there are blue spots on the abdomens of the males.
The Southern Hawker Dragonfly breeds in still or slow-flowing water, however, they will wander widely and are often seen in gardens and open woodland. This is an inquisitive species and will approach people.
The adult eats various insects, caught in flight. The nymphs (larvae) feed on aquatic insects, tadpoles and small fish ambushed in the pond they frequent until they emerge as adults in July and August after two to three years of development. The larvae can only see a short distance but they are very sensitive to movement. On the underside of their heads they have a hinged jaw called a ‘mask’ that can be flicked out to catch a passing insect or fish. The larvae have gills and so do not need to surface for air.
The Southern Hawker Dragonfly is a large, brightly coloured Dragonfly. The males are often seen patrolling by a ponds edge or river, where they fight away intruders, crashing into rival males and spiralling through the air. The females are quite conspicuous when they lay their eggs, but they sometimes give away their spot by clattering up from the reeds. They lay their eggs on moss, reeds or rotten wood. The males are sometimes very curious and come flying up to you.
The Four-spotted Chaser Dragonfly, known in North America as the Four-spotted Skimmer (Libellula quadrimaculata) is a dragonfly of the family Libellulidae found throughout Europe, Asia and North America. In the United Kingdom, the adult dragonfly is found between April to early September.
The Four-spotted Chaser Dragonfly is one of the commonest dragonflies in Ireland.
The Four-spotted Chaser Dragonflies have a small brown patch on the middle of the leading edge of each wing, this combined with the dark pterostigma (a coloured, chitinous patch on the outer region of each wing) is the origin of the name ‘Four-spotted Chaser’. They have a brown tapering abdomen, becoming black towards the posterior end and yellow markings on the sides of the abdomen. There are dark brown patch at the base of the wings. Larvae have a two year developmental cycle. Adults feed manily on mosquitos, gnats and midges, the larvae feed primarily on other aquatic insect larvae and on tadpoles.
The male Four-spotted Chaser Dragonfly is considered to be highly aggressive and will defend a given territory from invasions from other males of the species. The male is known to have a preference for prominent perches and will often return to the same perches around the margins of lakes and ponds whilst it patrols for intruders. Both male and female are strong fliers and mating takes place in the air, rather than on perches or amongst the vegetation. The female lays her eggs on floating vegetation.
The Four-spotted Chaser Dragonfly may be confused with females and immature males of the Broad-bodied Chaser (Libellula depressa) and the Black-tailed Skimmer (Orthetrum cancellatum), however in the latter two species there is no dark spot on the middle of the leading edge of the wings.
Some common species of dragonfly in the Northern Hemisphere:
Keeled Skimmer (Orthetrum coerulescens)
Black-tailed Skimmer (Orthetrum cancellatum)
Migrant Hawker (Aeshna mixta)
Azure Hawker (Aeshna caerulea)
Norfolk Hawker (Aeshna isosceles)
Common Hawker (Aeshna juncea)
Red-veined Darter (Sympetrum fonscolombii)
Common Darter (Sympetrum striolatum)
Vagrant Darter (Sympetrum vulgatum)
Yellow-winged Darter (Sympetrum flaveolum)
Broad-bodied Chaser (Libellula depressa)
Scarce Chaser (Libellula fulva)
Green Darner (Anax junius)
Downy Emerald (Cordulia aenea)
Blue-eyed Darner (Aeshna multicolour)
Roseate Skimmer (Orthemis ferruginea)
Widow Skimmer (Libellula luctuosa)
Great Pondhawk (Erythemis vesiculosa)
Comet Darner (Anax longipes)
Banded Pennant (Celithemis fasciata)