25 Interesting Facts About Dragonflies

1. Dragonflies belong to the Odonata group of insects. The other member of this insect family is damselflies. Fossils indicate that dragonflies are more than 300 million years old.
2. Dragonflies and damselflies look similar, but they have several visible differences. Dragonflies have large eyes and bulkier bodies as compared to damselflies. The shape and resting position of wings is also different in both these insects. (Source)
3. There are around 3,000 extant species of dragonflies. They are commonly found near freshwater habitats in all continents except Antarctica.
4. A species of dragonflies holds the record for the world’s longest insect migration. This 4 cm long dragonfly covers a distance of 14,000 to 18,000 km during its annual migration while flying at an altitude of 1,000 m. Monarch butterflies cover 8,000 km during their annual journeys, the second-longest insect migration. (Source)
5. Dragonflies can fly in forward, backward, vertical, and zigzag directions. Their flying speed at the forward movement is up to 35 mph. They have four wings and their rear wings are larger than the front wings. Dragonflies can beat their wings 1,800 times per minute, which assists them in hovering. (Source)
6. Dragonflies are bio-indicators of the health of an ecosystem, as they need clean water and the necessary oxygen level to survive. Pollution and non-native vegetation have endangered 10% of dragonfly species.
7. The mating process of dragonflies (and damselflies) is unique among insects. They form a heart or wheel posture while mating.
8. Like other insects, dragonflies have six legs. But unlike other insects that use these legs for walking or swimming, dragonflies use their legs only for catching prey. They have lost the locomotion function of their legs.
9. Dragonflies are large compared to the majority of insects. The range of their wingspan is from 20 mm (0.8 in.) to 16 cm (6 in.).
10. People in Bali (Indonesia) habitually eat dragonflies as food. These insects are easily available from the terraced rice paddies in this area. (Source)
11. Dragonflies are carnivore insects during their nymph and adult stages. They commonly eat mosquitoes, midges, butterflies, bees, flies, and even tadpoles. They can catch their prey mid-air and eat food equal to their weight daily.
12. There are several predators of juvenile and adult dragonflies. Ducks, amphibians, and fish hunt young dragonflies. The predators of adult dragonflies include reptiles, fish, and small mammals. Apart from animals, some meat-eating plants can also consume and digest dragonflies. (Source)
13. Dragonflies are known as the most successful predators in the animal kingdom. They catch 95% of their prey, while this rate is 25% in lions and 50% in great white sharks. After capturing prey, the dragonfly devours it in a few seconds by using its sharp teeth.

    

    Dragonflies spent most of their life as nymph

    
    
14. There are two stages in the lifespan of dragonflies. They live as nymphs for 1 to 3 years when they stay in the water. The adult stage lasts only for a month or so. Only adult dragonflies can fly.
15. Compared to tri-chromatic vision in humans, dragonflies have between 11 and 30 visual opsins. It allows the insect to view ultraviolet and polarized light. They also have better color discrimination as compared to humans. (Source)
16. Dragonfly eyes have a 360-degree visual field and can detect prey’s fast movement. Scientists are using these qualities to develop bionic eyes and driverless cars.
17. Dragonflies are one of the few animals that can deploy the motion camouflage technique while attacking their prey. (Source)
18. Dragonflies don’t and can’t sting humans. They usually don’t bite humans unless for a defensive purpose. These bites are mostly harmless, and only large dragonflies can break human skin. (Source)
19. The gills of dragonflies during the larval stage are inside their rectum. They absorb oxygen from the water through these gills.
20. More than 80% of a dragonfly’s brain is for processing visual information. Few species can see objects 30 ft. away and detect a movement 60 ft. away. These qualities help them to eat a large number of pests regularly. It makes them an ideal natural pest-control insect. (Source)
21. Extinct dragonflies were extremely large. The largest known insect present in prehistoric earth was a dragonfly. This dragonfly (Meganeuropsis permiana) was present on earth around 275 million years ago. The size and weight of this dragonfly were equivalent to that of a crow.(Source)
22. Scientists have managed to grow super-sized dragonflies in the lab. After living in chambers with high oxygen levels, these dragonflies become 15% larger than normal. (Source)
23. Dragonflies can effectively regulate their body temperature. They can do so by controlling metabolic heat and heat loss through alternation in their flight and circulation processes. (Source) 
24. The jaws and lower lips of dragonfly nymphs are very frightful. These mouthparts have inspired the creation of terrifying Hollywood monsters. (Source)
25. Dragonflies are sometimes infected by parasites, including blood-sucking mites and egg-eating fairy wasps. The fairy wasps are the smallest known insects in the world.