Dragonflies and Damselflies: Learn the Difference

Look at almost any body of water during the summer and you will see thin-bodied, large-winged, jewel-toned insects darting over the surface of the water.

A Halloween pennant dragonfly. (Photo by Glenn P. Knoblock)

Dragonflies! Or are they? What you think is a dragonfly may actually be a damselfly. They have many similarities, but once you know the differences, it is easy to tell which is which.


Dragonflies and damselflies are two of the oldest groups of flying animals. They have existed for 250,000 years and belong to the same order – Odonata, which means “tooth jawed.” Within this order are two suborders – Anisoptera, meaning “unequal winged” (dragonflies) and Zygoptera, meaning “equal winged” (damselflies). So, there’s one similarity (their jaws) and difference (their wings) just in the name. But let’s dig a little deeper into what those names represent and also find out about other similarities and differences.


Life cycle


Dragonflies (dragons) and damselflies (damsels) both start their lives underwater as eggs. They don’t hatch with wings, ready to fly. Instead, they are in a wingless, larval formal called nymphs or naiads.

Damselfly and dragonfly nymphs. (Photo by Chad Merda)

Dragon nymphs can live underwater for up to four years, depending on the species. During this time, they will molt up to 15 times as they grow. Damsels mature more quickly. It can take anywhere from a few weeks to a year depending on the species, water temperature and conditions. Like dragons, damsels molt during this time. Molting is the shedding of the outer layer of skin to expose a larger, looser skin underneath that it will grow into over time. The periods between molts are called instars.


Dragon and damsel nymphs have in interesting way of moving around. They use their six legs to walk, but also have jet propulsion capabilities thanks to their gills! Gills do the same job for some underwater creatures as lungs do for humans. Animals need oxygen, just like humans. When humans breathe, their lungs take oxygen from the air and send carbon dioxide out through the air. Dragons and damsels take in water. Then their gills take oxygen they need out of the water and let water they expel carry away carbon dioxide. Contracting their rectal muscles forces water out of their rear ends, which allows them to shoot forward.


Dragons have internal rectal gills that cannot be seen. Damsels have external gills that resemble a three-tined forked tail. Dragon nymphs are generally larger than damsels, but it can be hard to compare because they can be at different instar stages between molts when seen. Looking for the gills is the best way to tell them apart.

Once a dragon or damsel nymph has fully matured, it emerges from the water, then climbs onto a plant stem and sheds it final skin. You may be able to find these shed skins clinging to plants at the edge of waterways. Dragons and damsels continue to cling to the stem as their wings expand and bodies dry. They need to be completely dry to fly.


Adult dragons and damsels concern themselves with hunting and finding a mate. Dragons can mate while flying. Once mating has occurred, females lay their eggs in the water. Males usually continue to hold on to the females behind their heads and at the tip of their abdomens while they are laying eggs.

A mating pair of familiar bluet damselflies. (Photo via Shutterstock)

Damsels usually mate in vegetation then lay their eggs in the stems of plants that are emerging or floating on the surface of the water, or even on underwater plants. This may be because they are smaller and weaker fliers and do not want to be vulnerable to predators while mating.


Wings and things


While dragons and damsels do resemble each other, they have some differences that will help you identify which is which. Typically, dragons are bigger and bulkier, while damsels are smaller, more slender and more delicate looking.

A dragonfly's eyes are fused. (Photo via Shutterstock)

Dragon and damsel eyes take up most of their head. Dragons have two compound eyes that are fused at the top of their head. Damsels also have two large compound eyes, but theirs are separate, not fused together like dragons. They also have three simple eyes that form a triangle near the top middle of their heads.


Those large, compound eyes are each made up of 28,000 lenses. For comparison, human eyes only have one lens each. Because of this, dragons and damsels can see more colors and details than humans. They can also see in almost all directions at the same time, which is very helpful when hunting for prey and looking out for predators.

Damselflies have two separate eyes and three simple eyes near the top of their heads. (Photo via Shutterstock)

The middle part of their body is called the thorax. Wings and legs protrude from the thorax. Dragons and damsels both have six legs and two pairs of wings. Dragons’ fore and hind wings are a slightly different shape. Their front wings are wider than their hind wings. Damsels’ front and hind wings are the same shape. Wings can move separately from each other, which allows dragons and damsels to change directions quickly and even fly backwards. They dart and zoom quickly over and around the surface of the water. As the stronger fliers, dragons can fly higher and faster than damsels, often at or above our eye level, which also makes them easier to see.


Damsels fly in a fluttery fashion, resembling butterflies. They are weaker fliers, and they usually fly just above the surface of the water or around vegetation.


Probably the easiest way to identify if you are seeing a dragon or damsel is to watch them when they land. Dragons rest with their wings open flat. Damsels rest with their wings folded closed behind their bodies.


Hunting


Dragons and damsels are incredible hunters, both as nymphs and adults. They have a hinged jaw, edged with hooks. Their jaw takes up most of the bottom of their head and can extend almost the full length of their body. Nymphs approach their prey and then shoot out their jaw like a drawer to snare it and pull it back to eat. They hunt tadpoles, small fish and insects.


As adults, dragons and damsels hunt for insects. Using their long, bristly legs like a basket, they scoop up insects flying over the water’s surface or hanging out on shore plants. Then they cut them up with the hooks in their jaws and eat them alive. They will hunt any insects smaller and weaker than themselves, such as mosquitos, gnats, flies and even damselflies! You read that correctly, not only will dragons eat damsels, but damsels will also eat other damsels!


But dragons and damsels need to beware. While they are hunting, they are also being hunted. They can fall prey to birds, frogs and even spiders that can snare them in webs made in vegetation at the water’s edge.


Meet some common Will County dragons

A common green darner. (Photo via Shutterstock)

The common green darner is nicknamed the “darning needle” for its needle-thin body and large wings. It is about 2 3/4 inches to 3 1/8 inches long and has a green thorax, violet-blue abdomen and clear wings. It is most commonly found around ponds and streams and will even venture into fields that are near a water source. Common green darners are one of the fastest-flying dragons.

An eastern amberwing. (Photo courtesy of Lorenzo Pesce)

The eastern amberwing is nicknamed the eastern pondhawk for its mosquito-hunting prowess. At only about 1 inch long or less, it is one of the smallest dragons in the U.S. Its brown body and short, stubby orange to amber wings are said to mimic a wasp’s appearance. This could be an adaptation meant to deter predators. It is mostly found around small ponds, ditches and wetlands.

A Halloween pennant. (Photo courtesy of Debi Shapiro)

The Halloween pennant is named for its coloring. With an amber head and body and yellow wings with brown stripes and spots, it would blend right in with the orange and black decorations associated with Halloween. This color pattern also resembles monarchs, and Halloween pennants have a fluttering flight similar to butterflies, which could be an adaptation to trick predators. It is mostly found at the borders of weedy wetlands and open areas and fields.

A white-tailed skimmer. (Photo via Shutterstock)

The white-tailed skimmer is named for its white abdomen, which can resemble a tail. It is almost 2 inches long with a grayish-brown thorax with white or yellow spots. Its wings have a dark band near the tip. White-tailed skimmers can be found in ponds and streams.


Meet some common Will County damsels

An ebony jewelwing. (Photo by Anthony Schalk)

The ebony jewelwing is named for its distinct black wings and jewel-toned, metallic green-blue body. Females have white spots on their wing tips. This delicate damsel is about 1 3/4 inches long. It can be found around babbling brooks and show-moving rivers and streams with overhanging vegetation that can provide protection from predators.

A familiar bluet. (Photo by Glenn P. Knoblock)

The familiar bluet is one of the brightest blue damsels. It is about 1 1/4 inches long and has a blue thorax and blue and black striped abdomen. Familiar bluets can be found in any body of water — lakes, ponds, bogs, rivers, even large puddles!

An eastern forktail. (Photo by Glenn P. Knoblock)

The eastern forktail is the most common damsel in Will County. This damsel is about 3/4-1 1/4 inches long and mostly green and black — green and black face, black thorax with two lime green stripes and a black abdomen with a blue tip. It can be found in most areas that stay permanently wet.

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