Flying Dragons

After a delay, they finally repaired the pump for our swimming pool. The next morning, I removed the skimmer cover, and what did I see? A dragonfly! A female common green darner (Anax junius). It was dead. The most perfect specimen I have ever seen. I retrieved it and set it out to dry. Soon it will crumble. I will always cherish the photo.

Flying Dragons
by Anita Carpenter

On a sunny, unusually warm, late October day, I discovered a tiny red dragonfly basking on my mailbox. Dragonflies shouldn’t be flying this late in the year – or so I thought. My curiosity was piqued.

This individual, a male, was the smallest dragonfly I had ever seen. It measured about 1-1/4 inches with a wingspan that barely exceeded that. It had a red face, thorax, and abdomen – along with yellow legs. If this individual had been a female, she would have been brown but, as she aged, she may have turned red, although not as red as a male.

Historically, this dragonfly was named the yellow-legged meadowhawk for obvious reasons. Its common name, which has since been changed, now seems to pay homage to its seasonality – the autumn meadowhawk (Sympetrum vicinum).

The autumn meadowhawk is just one of nine meadowhawk species found in Wisconsin. The other eight species all have black, not yellow legs, and small black triangles on both sides of their abdomen. (The eight species differ in other characteristics.) The autumn meadowhawk is noteworthy because it has the latest flight period, July into October, of all other dragonflies and is likely to be the last dragonfly to be seen in the year.

One of the interesting facets about this late-flying dragonfly is that the timing of the stages in its life cycle differs from most other dragonflies.

To understand the difference, we need to study the stages in a dragonfly’s life cycle. In spring and early to mid-summer, we observe most dragonflies flying, maturing, defending territories, mating, and laying eggs. Depending on the species, females lay eggs in water, or on sediment, or inserted into underwater plant stems. In most dragonflies, the eggs hatch within a few days. Each larva grows by molting its “skin” ten to twelve times throughout summer and winter.

During its second-to-final molt, the larva stops feeding and transforms into a dragonfly but is still encased within its larval skin. When spring or early summer arrives (depending on the species), the last-stage larva crawls out of the water and climbs up a plant stem or vertical surface. The larva swallows air which causes the back of the larval skin to split open. Slowly the dragonfly emerges. Its legs harden first. Then the insect pulls its abdomen and crumpled wings out of its skin. The abdomen elongates and swells, the wings lengthen, stiffen, and then lower to their horizontal position. The entire process may take from one to three hours, and soon the insect is a free-flying adult dragonfly, and the cycle repeats itself with a new generation of dragonflies. Emergence is a critical period in the life of a dragonfly, because this is when it is most vulnerable to predation because it can’t fly to escape.

The stages of an autumn meadowhawk’s life cycle are similar but differ in their seasonal timing. Because they have the latest flight period, July into September/October, mating and egg-laying are later in the season. Consequently, females deposit their eggs in mud or wet moss along the shore. The eggs do not hatch before winter but remain as eggs until spring rains and high water arrives. Then the eggs hatch, with larval development occurring during spring and summer (not fall and winter). Therefore, this year’s adults emerge from late July into August/September. By this time, other dragonflies have completed their reproductive cycle, whereas autumn meadowhawks are just starting theirs.

Discovering an autumn meadowhawk in late October is not as unusual as I had originally thought.

I’m grateful that this beautiful, delicate, little autumn meadowhawk paid me a surprise visit that piqued my curiosity. I’m always excited to see and learn something new.@

Read Prehistoric Insects for another dragonfly adventure.

The Home page image for this blog post is the female common green darner (Anax junius). It’s known for its impressive size and distinctive coloration, with the thorax being a bright green, and the males having a bright blue abdomen, while females have a reddish-brown abdomen.