In prehistoric times dragonflies were much larger, the largest flying insects ever. The largest member of the extinct Protodonata was the Permian Meganeuropsis permiana with a reconstructed wingspan based on fragments, scaled to complete fossils of similar animals of about cm. All the links in this answer take you to photos, displayed in a new browser window, outside the BDS web site. Average cruising speed is probably about 10 mph.
Small species, and especially damselflies, are generally slower, although many medium-sized species can probably keep up with the largest ones. When dragonflies and damselflies first emerge from their water-borne larval stage, most have very muted colours.
Depending on weather conditions, it can take a few days for them to gain their bright adult colour. Common Blue damselflies are often a pale pinkish-brown rather than sky-blue on first emergence.
Some damselflies undergo a gradual colour change as they age, for example the Blue-tailed Damselfly. The females have several different colour forms and some change from violet to rich brown while others go from salmon-pink to blue. Some of the larger dragonflies also change colour as they age.
Older females may start to develop the colouration of the males. Examples are Common Darter , which goes from yellow-brown to reddish brown, and Black-tailed Skimmer , which goes from yellow-brown to a blueish-grey. Greatly simplified, the life cycle is Egg usually laid under water , Larva free moving, water dwelling nymph and Adult.
The larva lives for several weeks or years depending on species underwater and undergoes a series of moults as it grows. Mainly, adult dragonflies eat other flying insects, particularly midges and mosquitoes. They also will take butterflies, moths and smaller dragonflies. There is one Asian species which takes spiders from their webs! The larvae, which live in water, eat almost anything living that is smaller than themselves.
The larger dragonfly larvae are known to catch and eat small fish or fry. Usually they eat bloodworms or other aquatic insect larvae. Dragonflies certainly do eat large numbers of flying pest species, but using them to control these pests is not really feasible.
There have been a number of studies carried out and only in very restricted and tightly controlled environments have Dragonflies, or their larvae, been shown to be able to control pest numbers. In the open, there is no reason to suppose that Dragonflies introduced to a pest rich habitat will stay there. Indeed, they certainly will not if other aspects of the environment do not suit them.
It follows from this that your best chance of getting Dragonflies to prey on pests is to develop the habitat so that it is particularly suitable for Dragonflies, a worthwhile aim in itself! Dragonflies do have enemies. Among the species that catch and eat adult dragonflies and damselflies are birds e. Wagtails and Hobbies , Spiders many damselflies are caught in webs , Frogs, and larger species of dragonflies which catch and eat other dragonflies and damselflies.
In the larval stage, which is spent underwater, they are preyed on by fish, frogs, toads and newts, other water invertebrates — and Kingfishers see photo below. Their defences include their excellent eyesight and flying skills which can help them to evade capture.
Some are coloured black and yellow, or black and red, which is the universal warning colouration and may deter some of the bird predators. There are many legends and myths about dragonflies and damselflies from all parts of the world. Many are evident from their common nicknames.
This name may come from the way a captured dragonfly curls its abdomen as if in an attempt to sting. Another possible explanation of this name is that the big Aeshnids etc. Here they were actually feeding on the flies attracted to the horses. People seeing it made the inference that it was the dragon, being big and obvious, stinging, rather than an unseen fly biting.
Naturally there is no truth in either myth Similar myths are found throughout the world. You can find more about them by visiting Cultural Odonatology References , a site which has reference material relating to myths, legends, folklore and cultural significance of Odonata throughout the world.
For more myths, and mythical names used in Europe you could visit Swedish Dragonflies where you will find a page of such items. Both these links will open in a new window.
Yes, Dragonflies do have a pair of antennae. They are very tiny and difficult to see. If you look at the photo you will just be able to see the antennae between the front of the eye and the front of the face of this Emperor dragonfly.
As dragonflies rely much more on their eyesight than on a sense of touch or smell, they do not need the large antennae found on some beetles and moths. Several species of dragonfly are known to collect in large aggregations or swarms. In most cases this appears to be due to very favourable feeding conditions in the locality. This is less likely as males are much more aggressive to each other when looking for a mate. The Four-spotted Chaser occasionally collects in these large aggregations before making a mass movement to another locality like a bird migration.
The reasons for this are unclear but may be due to population pressures. There are records from the US of migratory assemblages of species such as the Green Darner Anax junius and various species of Saddlebags Tramea. It is laying eggs. While damselflies and some dragonflies will settle on vegetation and insert eggs into stalks and other material in or near the water, many dragonflies will fly across the water dipping the end of their abdomens into the water and releasing eggs.
These eggs are surrounded by a jelly-like substance which enables the eggs to stick to vegetation or the bottom of the pond. Some species will remain paired while the female does this, while in others the male will fly nearby to guard the female from the attentions of other males. Dragonflies have extremely good vision, which they use to locate and catch small insects in flight.
Like most insects, they have compound eyes. In the case of dragonflies the eyes contain several thousand individual facets, each containing a tiny lens. Adult damselflies have a long and slender abdomen, two pairs of wings and three pairs of long legs. Adult damselflies live near streams, lakes and ponds. The larvae live in streams, lakes and ponds among plants and rocks. Adult damselflies eat mainly flying insects. Larvae eat insects in the water, worms, and occasionally small fish.
Adult damselflies breathe by drawing air into special breathing tubes in their bodies. These tubes are called spiracles. Larvae breathe through three long leaf-like gills at the end of their body.
They both have relatively large eyes, but small, underdeveloped antennae. Damselflies Zygoptera. Damselflies are smaller and stay close to the water. Their two pairs of wings are equal in size and are held against their body at rest. Their eyes are separate. What do Dragonflies and Damselflies Eat? They are carnivorous and will eat any small insect, but their diet is mostly midges and mosquitoes. The larvae are voracious eaters and will eat anything they can catch, usually other aquatic larvae and bloodworms.
What Eats Dragonflies and Damselflies? Common predators of dragonflies and damselflies are birds, spiders damselflies are caught in webs and frogs. The larvae are eaten by frogs, toads, newts, fish and kingfishers. Why Are They Important?
The British Dragonfly Society has just launched the Dragonflies in Focus Project , a 5-year recording project that will eventually produce the National Dragonfly Atlas. There is evidence that dragon and damselflies are emerging earlier in the spring and new species, such as the Small Red-Eyed Damselfly are becoming established in the UK.
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