Dazzling Dragonflies

In 2011 I posted about some beautiful dragonflies that laid claim to the water in our out-of-commission swimming pool. I attempted to identify them but it turned out that my visitors were actually exotic recent newcomers from Africa and not the common-or-garden relative species I labelled them as. I would have remained in ignorance had it not been for guidance from some knowledgeable and generous people who took the time and trouble to (most tactfully), correct me, for which I thank them. I decided to ‘reblog’ the post but this time giving the correct identifications and to remove the misleading old one. I’ve timed the posting so anyone planning to visit the area imminently, either seeking, or happening upon any of the species is armed with better information.

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Late August and early September see the emergence of a variety of species of dragonfly and in 2010 we had regular visits to our garden from some glorious and somewhat exotic ones. Their presence was compensation for our swimming pool being unusable for its proper purpose. The pump wasn’t working, so despite the intense sun it had remained partially filled with water as we were unable to drain it out and the garden sprinklers regularly topped it up each evening. The dragonflies adopted it as their territory, patrolling its surface and keeping watch for intruders whilst basking on the pool edge. There were three species that were very conspicuous, two that were red and one blue, all adult males.

ORANGE-WINGED DROPWING- Trithemis Kirbyi

family Libellulidae other common name is Kirby’s dropwing

Orange-winged Dropwing in obelisk posture

The first one to arrive was a bright scarlet red Orange-winged Dropwing (Trithemis Kirbyi) that spent quite long periods on the very edge of the pool, lifting his body vertically to into what is known as the obelisk posture.

The bright sunlight cast perfect reflections of the extensive orange patches on both the fore and hind wings of the insect.

The obelisk posture is one that some dragonflies and damselflies assume to prevent overheating on hot sunny days. The abdomen is raised until its tip points at the sun, minimizing the surface area exposed to solar radiation. When the sun is close to directly overhead, the vertical alignment of the insect’s body suggests an obelisk. 

The Orange-Winged Dropwing is an African species  which over the last few years has begun to establish itself in Southern Spain. Adult length is 3.2-3.6 cm; wingspan 5.8 cm. The males are virtually all red, apart from black pterostigma, the blue-grey lower half of the eye, and the very large orange wing patches. The female has a similar wing patch, but its size is more variable than in males and the base colour is yellow, as it is in immature males.

One of the most common African dragonflies, its natural habitats are various; subtropical or tropical moist lowland forests, dry savanna, moist savanna, subtropical or tropical dry shrubland, subtropical or tropical moist shrubland and rivers.

4/9/10- The Orange-winged Dropwing has a vivid orange patch at the base of the forewings as well as having the orange patch at the base of the hindwings

Wandering around the garden I was attracted to the dragonfly in the following photograph when I spotted something glittering in the sunlight: it was perched on a lavender flower and stayed there for some time. It was clearly a ‘fresh’ specimen an immature male, I think, although females are similar to this.

8/9/10- Orange-winged Dropwing- immature male

The Orange-winged Dropwing had the ‘territory’ to himself for a week or so, but then two individuals of different species arrived on the scene and also became very regular visitors. One of these was also red coloured, but a darker red with purplish shading whose common English name is Violet Dropwing (Trithemis annulata). The  other a powdery-blue Epaulet Skimmer (Orthetrum Chrysostigma).

The behavioural dynamic between the three males was interesting. The Orange-winged Dropwing was always the first to appear, then later the Violet Dropwing and the Epaulet Skimmer would arrive in the garden at virtually the same time and settle themselves in positions on the edge of the pool, sometimes virtually next to one another. There was no sign of any aggression or territorial disputing between them at all. However, the Violet Dropwing did chase the slightly smaller Orange Dropwing whenever it flew out over the water or generally got too close.

VIOLET DROPWING – Trithemis annulata

family: Libellulidae other common names are violet-marked darter, purple-blushed darter or plum-coloured dropwing

The adult male Violet Dropwing has a blue pruinescence overlying a scarlet body that creates a purplish-violet colour that is unlike that of any other dragonfly in Europe.

Violet Dropwing (Trithemis annulata) has distinctive red veins & an orange patch at base of hindwings

Adult length is 3.2-3.6 cm wingspan: 60 mm (2.4 in). The mature male has a dark red head and a yellow labium with brown central spot. The eyes are red with white spots on the rear edge, and the frons is dark metallic purplish-red.

Violet Dropwing perched on car ariel

The wings have distinctive red veins, the pterostigma is orange-brown and there is a large orange-brown splash at the base of the hind wings. The abdomen is fairly broad and is pinkish-violet, with purple markings on the top of each segment and blackish markings on the terminal three segments. Females are a similar size to males but the thorax is brownish and the abdomen is yellow with dark brown markings. The wings of females lack the red veins of males but have similar orange-brown patches.

Violet-dropwing-trithemis-annulata

EPAULET SKIMMER  Orthetrum Chrysostigma

family Libellulidae

Longer established in Iberia than the Dropwings, the Epaulet Skimmer is one of a number of dragonfly species where the mature male is predominantly blue and the female/immature male is predominantly a tan/brown colour.  The wings have a reddish-brown costa and brown pterostigma.

4/9/10-Epaulet skimmer -Orthetrum-chrysostigma

The Epaulet Skimmer is widespread throughout the Sahara region in Africa; it’s larvae are able to survive in moist sand, suggesting that it is an insect very well adapted to surviving in an arid landscape. 

4/9/10-Epaulet skimmer- Orthetrum chrysostigma

The Epaulet skimmer is unique amongst the Skimmers occurring on the Iberian peninsula in having a single white stripe or “epaulet” outlined in black on each side of the thorax, which is just about visible in the enlarged photograph below.

The Epaulet Skimmer has a diagnostic white stripe on the side of the thorax

length: 39 to 46mm flight period in Iberia: late March to mid December habitat: marshes, streams, & pools in open terrain, plus man made water bodies distribution: Southern Portugal & Spain, North Africa & the Near East. Not uncommon in southern Portugal and Spain, currently absent from the north of the Iberian peninsula, but perhaps expanding it’s range in that direction.

A week or so after the arrival of the three adult males described above I began also to notice cast-off dragonfly larval ‘skins’ stuck to the inner walls of the swimming pool. Each morning there would be a few more, but several days passed before I was out early enough to witness a dragonfly still preparing for its first flight. I believe it was an Epaulet skimmer as it had the distinctive white stripe on its thorax.

8/9/10- An emerging dragonfly on wall of pool is probably an Epaulet skimmer

I am relieved that all the new dragonflies emerged and set off into the world before the swimming pool was emptied and cleaned and rather wished it could have been left as a pond.

Update on species 2015:

The presence in Southern Spain of all three species described above is now sufficiently established for them to be included on many species lists for the area and their ranges are extending year on year.