Saturday 23 January 2010

The Dark One

 

I have often seen this rather large, dark, mystic-looking dragonfly buzzing tirelessly at speed to and fro guarding its territory over an area of the stream.

Once in a while, another similar-looking dragonfly will enter this well-guarded space and a chase will ensue to get the intruder off the area before it returns to resume patrolling tirelessly over its territory again. Or perhaps it was a short, futile pursuit for a female dragonfly?

Anyway, once in a while this dragonfly will then stop to perch somewhere on a twig up high over the stream near the area it had been patrolling.

All those times, I could never get the chance at all to have a good look at the dragonfly to even look at any markings or features to enable its identification, much less get a photo.

And then, I had my lucky day! 

Well, I had plenty of time to spare!  So I sat down near its territory and just waited.  The first few times, when it stopped to perch, I couldn't even get close before it took off again.  But after some time, the "comfort distance" got closer and closer until it was enough to get a few good shots.

 

 

This dragonfly is the Zygonyx iris of the family Libellulidae.  It can be recognised by the yellow mid-dorsal stripes on its abdomen.  The male has hindwing length of 40-42mm and this species is widespread in tropical Asia.  In a sunlit spot, it looks dark and metallic with a bluish tint to it.

 

 

I also had the chance to observe a pair of the Zygonyx iris in tandem the other day and watch the practice of contact guarding during the oviposition process for this species.

The male and female dragonflies remain in tandem and the male maintains his clasp on the female even while she oviposits.  They will fly around at speed in tandem, then hover over an area and make rapid swoops down onto the submerged tree roots in the fast flowing stream, allowing the female to flip its abdomen in the water.  This is repeated over several different spots at intervals and then, just as suddenly, the pair breaks off and fly away on their own.

 

 

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