Stretching the stream DRAGONFLY BY GAURAV NAVALKAR

Name  Common Name : Dragonfly  Scientific Name: Anisoptera  Family : Eg: Aeshnidae (hawkers or darners) eg Blue spotted hawker  Order :Odonata

Description  Dragonflies are heavy bodied, strong flying insects that holds the wings horizontally when at rest  An adult dragonfly’s body is divided into head, thorax and abdomen.  The head is large with very short antennae and covered by very large two compound eyes  The mouth has a toothed jaw, a flap-like labrum at the front to catch prey  The thorax has 3 segments; holds two pairs of wings and three pairs of legs  The wings are long, veined and membranous, narrower at the tip, wider at the base  The abdomen is long and slender and has 10 segments  Dragonflies come in varying sizes; they are usually between 1-4 inches in length  Dragonflies come in bright colours – blue, green, red, yellow  Dragonflies are found near wetlands or near water.

Life Cycle

Life Cycle Egg & Nymph  The female dragonfly lays eggs in batches on moist surfaces, plants submerged under water or in water directly.  Dragonfly eggs are round and about 0.5 mm long  The eggs hatch usually within a week to couple of weeks. The time for hatching depends on the atmospheric temperature and the climatic surroundings.  The eggs hatch into larvae called nymphs which again live in water.  Nymphs have large eyes, 6 legs, - often flat on underside, - no tails. Their size ranges from 1/2" - 1 1/2“  Nymph stage is the longest stage in the life cycle of a dragonfly. This stage usually lasts anywhere from a year up to four years  Dragonfly nymphs are shorter and bulkier, and the gills are located inside the abdomen. They look spider like.  Nymphs shed their skin anywhere from 6 to 15 times during their life cycle

Life Cycle Adult Dragonfly  An adult dragonfly has a long body, transparent wings, and large eyes.  It has 6 legs, a thorax, a head, and an abdomen. The abdomen is long and segmented.  Even though the adult dragonfly has 6 legs, it cannot walk properly but is a fast flyer.  Size of an adult dragonfly may range from 1-5 inches  An adult dragonfly is the most colourful insect; colours range from blue, green, red, yellow  The adult stage could be the shortest life-cycle stage ranging from few weeks up to a year

Food Chain They eatThey get eaten by GnatsBirds MothsLizards FliesDucks ButterfliesFish

Habitat Dragonfly's live near wet lands and water They like to live in warm climates.

Adaptive Features  Dragonflies are well known for their speed.  They can move forward at a rate of roughly 100 times their own body length each second, sometimes reaching speeds of around 55 miles per hour.  They're also able to move backward, sideways and diagonally bit slowly.  Their speed and agility mean they can quickly zoom away from and outmanoeuvre any potential predators. It gives them an advantage when hunting for prey, too.

Interesting Facts  Many dragonfly species can get up to 7-8 cm long  Dragonflies at nymph stage live in water. This is the longest stage in their life-cycle. The nymphs have gills inside the rear of their abdomen. They obtain oxygen by contracting their abdomen to pump water in and out of the gill chamber.  Fossil Dragonflies have wing spans up to 2 metres and were almost a meter in length  Dragonflies hold their wings horizontally at rest  Dragonflies respire not only through their gills, but also through their wing pads.

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