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Posted by portugalpress on November 01, 2016
Most damselflies (and some dragonflies) share the role of finding ideal homes for the next generation and putting the children to bed
This dragonfly has emerged from its exuvia (right) and is preparing for its maiden flight in the summer sunshine.
Dropwing, one of the Algarve’s many beautiful dragonflies

Sue Parker explores uncharted territory between history and mythology

The natural history of ‘prehistoric times’ is documented in remarkable detail in fossil records; they tell us how recently mankind emerged as top predator and, intriguingly, who preceded us in this role. Most famous, of course, are the dinosaurs, the majority of which were wiped out in a mass extinction 65 million years ago. But other life forms once reigned supreme, chilling the hearts (and if not minds then perhaps wings) of lesser beings. These prehistoric monsters both predate and pervade the mythology of Man.

From the evidence available, we may infer that airborne fire-breathing dragons with lizard-like bodies and bat-like wings were as much flights of fancy as were giant ogres striding across landscapes in seven-league boots.

Heroic tales of dragons and damsels and dreadful dark deeds must have had some foundation in reality, however, because here in the Algarve their descendants still battle it out each spring and summer, creating misery and mayhem for those entrapped in dungeons with little prospect of escape.

Nearly 300 million years ago there lived groups of marauding insects now known as Meganeura and Meganeuropsis. Whereas today’s dragonflies have wings typically 5-7cm long, these early prototypes had wingspans up to 70cm, with the manoeuvrability to terrorise smaller insects (and possibly also reptiles) on which they preyed.

Today their descendants such as Blue Emperor Anax imperator and Violet Dropwing Trithemis annulata skim over the residual pools of Algarvian seasonal rivers, where mayflies, stoneflies, caddisflies and midges are easy pickings for these aerobatic maestros.

A dragonfly has a fascinating life history. From an egg laid in aquatic vegetation or deposited onto the water surface in late summer, a rather precocious little larva (sometimes referred to as a nymph or naiad) emerges and soon becomes a hideously aggressive and much larger larva.

Shedding its skin (exoskeleton) several times as it grows to maturity in typically a year or two but in some instances five years, this voracious killer feeds on other insects, worms, young newts – in fact anything smaller than or sometimes even larger than itself. Then, one summer’s morning, the nymph crawls out of the water, usually up a plant stem. In an hour or two, the winged adult crawls out of a final layer of skin (known as an exuvia). The dragonfly and its exuvia sit together on the stem; then just one of them takes to the air.

I can promise you this: you will not regret skipping the Jewellery Programme on daytime television to wander in the Algarve countryside and sit beside a stream to witness much finer sparkling gems perform this magnificent miracle of Nature.

Now where are those damsels? You missed them. You should have been here in early spring, when they danced in their hundreds before those evil dragons took over their watery world.

Damselflies are predatory insects related to dragonflies, but they are smaller, with slimmer bodies and, as the name suggests, they are more delicate creatures. Two pairs of gossamer wings make them almost as acrobatic as their larger, more conspicuous cousins, and at rest most damselfly species hold their wings along the body rather than, like dragonflies, mimicking World War One fixed-wing aircraft.

Damselflies have life-cycles similar to those of the dragonflies, but generally it is just a year from egg to egg-laying adult stage. Yes, I know that males generally don’t lay eggs … but damselflies are different. When it comes to tucking the children into bed (riverbed), the male is as deeply involved as his mate.

After mating, it’s lovely (if not love as we know it) that Mr and Mrs Damselfly still need one another. Using claspers at the back of his abdomen, the male attaches himself to the rear of the female’s head and, in this position, they fly together until they find a suitable patch of floating vegetation in the shallow margin of a stream. Then the female dips her abdomen below the surface to deposit a few eggs on plant leaves or stems. Next stop? Somewhere else very similar – another place that the damsel duo fancies will make a nice nursery for their dispersed family.

It’s teamwork, if not housework, and a male damselfly intuitively knows how to pull his weight (and the weight of his mate if, as often happens, she should take a tumble into the water).

Mr Damselfly is no more effeminate than a male ladybird … and equally unaware of any such connotation that his man-made name might convey to us.

Until the autumn rains swell those dungeon-like pools, and the rivers begin to flow again, both below the surface and in the air above, other insects have to watch out for dragons and damsels. And so can we.

By Sue Parker
|| features@algarveresident.com

Sue Parker is a Director of First Nature, Publisher of Algarve Wildlife – the natural year; Wildflowers in the Algarve; and Wild Orchids of the Algarve – how, when and where to find them.
www.algarvewildlife.com

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