Dragonfly vs Damselfly
Both dragonflies and damselflies belong in Order: Odonata of Class: Insecta sharing a number of features. Despite their similarities, the notable distinctions have been important in classifying them into two separate groups. By the look at them, it is not that easy to identify whether it is a dragonfly or a damselfly, as their minute antennae, large eyes, two pairs of wings with minute veins, and slender abdomen are almost same in both. Therefore, it is important to differentiate these similar looking insects.
Dragonfly
Dragonflies are predatory insects evolved 300 million years ago, which was before the evolution of flowering plants. They have about 3 – 10 centimetres long bodies, and the largest recorded dragonfly measured almost 20 centimetres. The two pairs of membranous wings are not similar; rear wings are larger and have a broad base than the front wings. Their wings are extremely important in identifying them as dragonflies, as well as in differentiating species within them. Dragonflies keep their wings positioned either horizontally or downwards when they rest. In addition, the venations of the wings are specific to each species in dragonflies. However, they have stocky bodies with sturdy abdomens. The large eyes are located very close to each other, almost contacting with each other at the top of the head. The male sexual organs are a pair of superior anal appendages, called claspers. Male transfers the sperm into female’s accessory genitalia, and he grasps her scruff to be in tandem. This interesting and unique process concludes with the sperm transfer as the female curls her tip of abdomen. Their eggs are round and the diameter is 0.5 centimetres. Dragonfly nymphs breathe from their rectal tracheal gills, and their bodies are short and bulky. After about 15 moults, the nymph becomes an adult, which lives only about two to three weeks.
Damselfly
Evolved before 300 million years, they are also living fossils. Damselflies are usually about 3 – 8 centimetres long, but there are records of more than 10 centimetre long damselflies. An interesting fact about their wings is that both pairs are similar in shape and size. Additionally, they keep their wings closed and upwards over the abdomen when they rest. Damselfly body is usually long and slender. They have eyes placed apart from each other, located on either side of the head. The males have two pairs of anal appendages to transfer sperms into females. The females have functional ovipositors. They spend some considerable time before mating; scientists believe female is assessing the male’s organs during this time before receiving a sperm from him. Damselfly eggs are cylindrical and about one centimetre long. Damselfly nymphs are long and slender and they breathe through caudal gills. Nymph becomes an adult after several moults, and the adult has a relatively shorter lifetime compared to nymph. However, in hot conditions, adults can live up to six months.
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What’s the difference between Dragonfly and Damselfly? – Both dragonflies and damselflies evolved before 300 million years, and are living fossils and have carnivorous food habits. – Dragonflies are slightly larger, and have abdomens that are sturdy and short. But, damselflies are little smaller, and the abdomens are long and slender. – Dragonflies keep their wings directed downwards or horizontally positioned, whereas damselflies keep them closed and upwards. – Additionally, the two pairs of wings in dragonflies are dissimilar, while those of damselflies are similar. – Eyes are closely located in dragonfly, while those are apart from each other in damselflies. – Eggs of dragonfly are round, but those are cylindrical in damselfly. – The nymphs of dragonflies are shorter and bulky, while damselfly nymphs are long and slender. – Apart from these visible differences, their sexual organs and gills of nymphs are also different in these living fossils.
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