Showing posts with label ischnura. Show all posts
Showing posts with label ischnura. Show all posts

Saturday, 8 May 2010

Dawn

I simply love the early hours of the morning. 

And I just do not tire looking at the dawn skies. 

The way the colours swirl and mix around on the palette of the sky is always different each dawn and always will be.

 

 

And just before the sun peeks out from the horizon, the colours become even more intense, giving you a glimpse of what to expect for the day to come.

 

 

In the cool of the early morning, these fishermen go out to sea to start on the day's catch.

 

 

And then, the sunrise!

 

 

The beginning of another hot day...

 

 

...as the sun rose higher in sky!

 

 

Life on the island begins to wake up.....

 

A bee has started collecting nectar.

 

While the Acisoma panorpoides is finding it difficult to get started.

 

A male Crocothemis servilia basking in the morning sun.

 

And another Crocothemis servilia getting warmed up to start the day.

 

Although still rather early, this pair of Ischnura senegalensis is already in wheel.

 

And life goes on.....

 

 

 

 

Monday, 22 March 2010

All Abuzz

 

There were dozens of the Diplacodes trivialis in the padi fields this morning.  And I really mean dozens!  As I walked along the bunds cutting through the fields, with almost every step I take, I would send a whole lot of them fluttering around to seek new perches.

 

 

A number of male dragonflies also kept busy engaging in aerial fights to chase away other males of the same species from their respective territories.

I took in the whole sight with a happy heart.  I have not seen so many of these dragonflies buzzing around in a while.  It was cloudy this morning... and in some places in Langkawi, there have been a bit of rain here and there in the evenings though it's been weeks since then.  Perhaps this is indicative of a change in weather patterns?  Perhaps that could explain the abundance of these dragonflies and all the activities? 

It was just the usual suspects up and about this morning.  The other species I spotted were Orthetrum sabina, Crocothemis servilia, Acisoma panorpoides, Brachythemis contaminata, Ischnura senegalensis, Pseudagrion microcephalum and Agriocnemis femina.  Yes, just a few species but there were lots of the Diplacodes trivialis everywhere, which made up for everything.

Anyway, one thing you can count on most days of the year is the Ischnura senegalensis.  Here's a photo of the male and 'andromorph' female in wheel position.

 

 

Apart from the dragonflies, it was also a morning for birds...

 

Little Egret - when breeding, it has long nape-, back- and breast plumes.  The nape plume can be seen in this photo below.

 

Chinese Pond Heron (I've just realised I took photos of the Chinese Pond Heron this same date last year...)

 

Baya Weaver

 

White-rumped Munia

 

Scaly-breasted Munia

 

 

Friday, 23 October 2009

Is This Funny?

Here's an interesting photo to share... 

Caught this pair of Ischnura senegalensis in the act recently.

 

 

Initially, I couldn't figure out what it was exactly that was going on as the first thing I noticed was the three sets of wings, meaning three damselflies.  Yet I could see the wheel position very clearly so what is that third damselfly doing?

Have a closer look here...

 

 

Seems like the female damselfly caught her food while within the male territory but before she could finish devouring her meal, the male damselfly caught up with her.  So here is the pair of them in wheel position with her half-eaten prey sticking out her mandibles!

And, yes, apart from mosquitoes and other flying insects, they do eat their own kind too.  It looks like this female Ischnura senegalensis had caught an Agriocnemis femina for lunch!  Or maybe it is an immature damselfly of the same species?

I can't decide... is this funny or what?

 

 

Monday, 31 August 2009

A Damselfly Ovipositing

In an earlier entry, I had a pair of damselflies of the species Prodasineura laidlawii in tandem, with the male hovering above and still clasping the female while she oviposits or lay her eggs in the fast flowing stream.

Well, not all damselflies do that.  It depends on the species and, sometimes, the circumstances. 

In one extreme, the male and female remain in tandem while the female oviposits and one such species is the Prodasineura laidlawii. On the other extreme, there are species where the male will not be around at all and the female would lay her eggs on her own.  The Ischnura senegalensis is like that.

Once copulation is completed, the male damselfly of the Ischnura senegalensis will let go of the female and fly away to perch elsewhere.  The female will then fly off on her own to find a suitable egg-laying spot and proceed to oviposit.

This picture here shows a female damselfly of the Ischnura senegalensis ovipositing in a grassy pond.

 

 

And here is another female of the same species ovipositing in a pond in the padi fields.

 

 

After ovipositing, the female will then find a perch to rest, bearing the muddy stains on her abdomen, which is often a tell-tale sign that she has been laying eggs...

 

 

Why is it referred to as ovipositing, you may ask? 

This brings us to the structure of the odonate body.  As mentioned in an earlier article, the males have accessory genitalia on the underside of the second segment (S2) of the abdomen.  The males also have superior and inferior anal appendages or claspers that emerge from the tip of the abdomen (S10), which is the last segment. 

Females odonates generally have shorter and stouter abdomens compared to their male counterparts and there is only a superior pair of appendages.  Females of some species have a sharp lance-like ovipositor on the underside towards the end of the abdomen, which is used to insert eggs into plant stems, rotting wood, wet soil or other plant materials.  While those of other species may have special flanges or non-functional ovipositors so there exists many different egg-laying strategies with different species of dragonflies and damselflies. 

Nevertheless, due to this structure in the female, when it dips its abdomen into the water or plants or roots to lay its eggs, it is referred to as oviposition.

 

 

Monday, 10 August 2009

Damselflies In Wheel

Dragonflies and damselflies have very unique and unusual mating behaviours.

Mating usually take place near ponds, lakes, streams and rivers as the majority of dragonflies and damselflies lay their eggs in water.  The male dragonfly will stake out an area that is a suitable egg-laying site and maintain patrol over this territory to defend it while looking out for a female mate.  Should another male of the same species enter this territory, a chase will ensue to get the intruder off.  Nevertheless, several different species can often be seen patrolling the same area. 

Courtship may be brief or nonexistent for many dragonflies and quite complex for most damselflies.  A mating pair is referred to as being "in wheel position" or in copula as their bodies form a rough circle, and almost a heart-shape sometimes, while mating.

Here's looking at a pair of Ischnura senegalensis in wheel position...

 

A mating pair may remain in the wheel position for a few seconds in some dragonflies and up to a few hours for many damselflies...

 

 

Friday, 24 July 2009

Ischnura senegalensis




This is one of the first damselflies I came across in the padi fields. 

It is the Ischnura senegalensis, of the family Coenagrionidae, and is sometimes referred to as the Senegal Bluetail or Common Bluetail because of the bright blue marking at the tip of its abdomen.

This species is common and often found in disturbed, open habitats including still and slowly flowing water.
It is very small in size.  And certainly tiny compared to the robust-looking dragonflies you usually see zapping around. 

To give you an idea, the hindwing length is 15mm for this damselfly.  The wings seem so delicate and the venation simply intricate.  Yes, it is hard to imagine something can be so tiny and yet have so many patterns and colours on it.

Female damselflies of this species are polymorphic in that they have different colour forms from the male, specifically olive and orange forms.  In addition, there is also an andromorph form like the male.
Mother Nature is truly amazing with her creations!


Ischnura senegalensis, female, olive form


 
Ischnura senegalensis, female, orange form