These ancient insects belong to the order of ‘Odonata’ meaning ‘toothed ones’. More about their mandibles at our July 24th workshop. Dragonflies are in the suborder Anisoptera (meaning ‘unequal wing’). Damselflies are in the suborder Zygoptera (meaning ‘paired wings’)
Ebony Jewelwing - Damselfly
Common Baskettail - Dragonfly
Let’s first talk about the differences between dragonflies and damselflies.
Family
There are 3 families of damselflies, Broad-winged Damsels, Spreadwings and Pond Damsels. There are 6 families of dragonflies, Darners, Clubtails, Spiketails, Cruisers, Emeralds and Skimmers.
Body
Damselflies are generally more slender having smaller and slimmer bodies than dragonflies. The bodies of Dragonflies are shorter and thicker.
Wings
In most damselfly species, their wings are normally folded along the body when at rest; whereas dragonflies hold their wings flat and horizontally. With damselflies, the forewings and hindwings, yes dragonflies and damselflies have 2 pairs of wings, are similar in size, hence the ‘paired wing’. A dragonflies’ hind wing is slightly broader than the forewings, hence the ‘unequal wing’. The wings then differentiate between dragonfly species. More about this at our July 24th workshop with Bob Bowles. But here is a peak; The hindwing triangles of Darners, Spiketails and Clubtails are elongated longitudinally along the length of the wing. The hindwing triangles for Cruisers, Emeralds and Skimmers are elongated transversely across the wing. This information helps immensely for identifying species.
Eyes
Damselflies’ eyes do not touch. They are set on either side of their head. Dragonflies, on the other hand, are different depending on species. Darner's eyes meet and run together for a distance. Spiketail's eyes meet only at one point, Clubtail's eyes are widely separated. Cruisers, Emeralds, and Skimmer's eyes meet in the middle. The eyes generally are much larger than the damselfly eye.
However they both have amazing eyesight with almost 360-degree vision, with one blind spot directly behind them.
Four-spotted Skimmer - Dragonfly
Calico Pennant - Dragonfly
Flight
Dragonflies are strong and agile flyers, zipping around flying upside down, backwards, straight up or down, sideways and they can hover. Damselflies are slower, flitting and fluttering about, having a more graceful appearance when flying.
More about their differences and similarities at our July 24th workshop.
Life Stages - Egg, Larva, Adult
Egg
Both species need fresh water to complete their life cycle. There are 3 stages: egg, larva (nymph) and adult. Each species requires a specific environment for its habitat from ponds, rivers and lakes to slow-moving streams, fast-moving streams and some even prefer marshy areas.
Most damselflies and some dragonflies inject their eggs into underwater stems or mud close to the surface of the water. Many dragonflies just lay their eggs in the water by the females dipping the tip of the abdomen into the water during flight. These eggs are laid daily over a period of several days and sometimes weeks. Most eggs hatch within 2-5 weeks with a few exceptions hatching the following spring.
Larva
The larvae live underwater typically for one to two years. There are some species that develop in two to three months and some can take up to 5 years. At this stage of the life cycle they are known as damselfly and dragonfly nymphs. This is where they spend the majority of their life, underwater. These nymphs are predators for mosquito larvae, aquatic insects, tadpoles and even small fish. During the nymph cycle, molting or shedding of the skin occurs several times. The final molt occurs out of the water. This stage is called Emergence. This transition is straight from a larva to an adult. The larva leave the water to find vegetation where the final molt into adulthood occurs. They redistribute body fluids, pushing the thorax, head, legs and wings out of the larval skin. Their legs harden, after a time, and then the abdomen is detached from the skin. The wings and abdomen, again after some time, expand and harden. The Emergence stage takes approximately an hour for Damselflies and three hours for Dragonflies. Known as tenerals, they are pale and vulnerable to birds, other predators and heavy rains. Many fish feed highly on damselflies and dragonflies as they emerge from the water.
Adult
It generally takes a few days to obtain adult colouration and sexual maturity. Their life-expectancy at this stage is very short, 1-2 weeks for these beautiful insects.
Aurora Damselfly - Pond Damselfly
Twelve-spotted Skimmer - Dragonfly
Photo Credits: Bob Bowles and June Crinnion
These amazing creatures are indicators, informing us of healthy water systems and changes in wetness in wetlands as they start to dry up.
Our first Dragonfly and Damselfly workshop is coming up for all ages on Wednesday, July 24, 2024 starting at 1:00 PM. Join Bob Bowles around the pond as we search for and learn more about these fascinating creatures. For more information please visit our website at https://www.robertlbowlesnaturecentre.com/programs
*Call for our Family Rate 249-385-6834
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