9 July 2010

damsels



Flitting round the garden at the moment are lots of Azure Damselflies, Coenagrion puella, in bright blue and iridescent green - around the ponds they are in a mating frenzy.  

(Damselflies are often mistaken for dragonflies but they are simple to tell apart, damselflies are smaller and when at rest fold their wings vertically - dragonfly wings are held stiffly horizontal)  

They begin their lives in the ponds as wingless aquatic nymphs, ugly little monsters with ferocious extendable jaws, they hunt small water creatures in the depths.  After a year hunting and growing the nymph matures in early summer, it climbs up a plant stem out of the water, the skin splits along the back and out emerges the winged flying adult.  The males are bright blue and the females green with an iridescent sheen.  The adults feed on small flying insects like mosquitoes.  To pair the male grips hold of the female's neck using a special clasper at the tip of his abdomen to hang on.  To mate the female bends her abdomen under and up to the males body.
 photo: Bohringer Freidrich         
After mating the pair fly together in tandem from floating leaf to floating leaf and the female uses her flexible abdomen to reach under the leaves to lay individual eggs.  In their pond the goldfish follow them eagerly, splashing about as they devour the freshly laid eggs.   
The males appear to stand stiffly 'on guard' while the female is busy laying down below and when approached too closely will drag the female into the air for a quick getaway.  I am disappointed in my 'up periscope' observations as I read the male hangs on simply to prevent other males mating with the female.
There are unidentified red damsels in the garden too.  They are proving far too quick for me and after working up a sweat chasing them about in the heat will be sitting in the shade till the weather cools.  We will all just have to imagine what they could be for the time being.

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