Singapore: Lion City Dragons

Singapore's Macritchie Reservoir is a great place to get on close terms with an array of damselflies and dragonflies.  Our walk around the boardwalk on March 4, 2012, described in my last posting, turned up so many that I have had to give them an entry of their own.  I'll start with a dragonfly I spotted just as we started our tour, one I had not seen before (and have never come across since).  It is Rhyothemis obsolescens, referred to among Singapore dragonfly-watchers as the Bronze Flutterer.

Odonate fanciers in Singapore, like butterfly-watchers, now have the advantage of an excellent guide: A Photographic Guide to the Dragonflies of Singapore by Tang Hung Bun, Wang Luan Keng, and Matti Hämäläinen.  I have found it very helpful, both in Singapore and in Malaysia.  Mind you, identification can still be tricky, especially with the damselflies.  As far as I can tell, this is a Blue Sprite (Pseudagrion microcephalum), a common Singapore species. The trouble is that there is another damselfly that looks almost exactly like it.

This, I think, is the other species, the Look-alike Sprite (Pseudagrion australasiae).  See the difference? No? I'm not surprised. Yes, there is a very slight difference in the intensity of the blue coloration, and that does match the photographs in the guide, but the clinching differences appear to be the width of the black band between the eighth and ninth abdominal segments (in other words, the thin black line crossing the large blue blotch at the end of the abdomen) and the length of the superior appendages, the two little prongs you can see sticking out the back of the tenth abdominal segment. In the Blue Sprite the black band is slightly wider, and the superior appendages are as long as the rest of the segment they are mounted on rather than somewhat shorter. If you feel confident that I have identified these species correctly (or incorrectly) then you undoubtedly know more about them than I do!

I think these are australasiae, too.  I say I think they are.

Now this one is a lot easier. It's a Crenulated Spreadwing (Lestes praemorsus decipiens), a member of the spreadwing family (Lestidae) and surely one of the few damselflies decorated with polka dots.  Like other spreadwings, it poses with its wings open rather than folded over the back as do most other damselflies.  

It's a particularly handsome and unusual-looking little creature, too (The authors of the dragonfly guide feature it prominently on their title page).  "Crenulated", by the way, means "having a margin with small rounded teeth".  It's usually used by botanists to describe certain types of leaves. Why it's been applied to this particular insect I haven't the faintest idea.

On to dragonflies.  We'll start with the large and striking Common Flangetail (Ictinogomphus decoratus), the commonest and easiest-to-find member of the goggle-eyed family Gomphidae in both Singapore and Malaysia.  

Of the dragonflies we found perched on the tips of emergent plants around the reservoir edge, it was the largest (and one of the most striking).

As usual, all of the other dragonflies here are members of the Libellulidae.  Neurothemis dragonflies are almost unavoidable in open country, as long a there is even a little water about.  These are males of Neurothemis fluctuans, known in Singapore as the Common Parasol.

One of the easier dragonflies to identify at Macritchie is the Sapphire Flutterer (Rhyothemis triangularis).    It is supposed to be an uncommon species in Singapore, and this was my first chance to get reasonably close to one.

It is particularly attractive when the light is right, and the dark patches in the wings are revealed to be an iridescent bluish-purple.

One of the most helpful features of the Singapore dragonfly guide is a section helping to distinguish between a number of very similar dragonflies with either red or blue bodies. With its assistance I was able to sort out several of the red-bodied ones, starting with the common Spine-tufted Skimmer (Orthetrum chrysis). In this case notice the grey eyes, red face and dark brown thorax; this is also one of the larger of the red dragonflies in Singapore.

A somewhat similar pattern but a very different body-shape marks this out as a Variable Sentinel (Orchithemis pulcherrima), probably a young male. This species also comes in a dark form, one that I had seen a couple of months earlier in the Panti Forest of West Malaysia.

The two black spots near the end of the abdomen identify this as a Scarlet Basker (Urothemis signata insignata).  Also notice the red eyes and wing veins. The top photo shows an individual in the so-called "obelisk position".

Here is a quite similar dragonfly, also in an obelisk pose.  This one has even more red-veining on the wings, though, and its abdomen is not so much red as a violent pink.  This is a young male Crimson Dropwing (Trithemis aurora).

In adult males the abdomen is fully pink, making it the most psychedelic-looking of Singapore dragons.

At the opposite end of the brilliance scale is this insect, perched flat against the trunk of a tree at the far end of the reservoir and trying to be as unobtrusive as possible.  Most libellulids don't perch like this, but this proved to be one anyway: a female Tyriobapta torrida, appropriately known in Singapore as the Treehugger.  This is a swamp forest dragonfly, quite unlike the open-country species we had seen up till now (it is, for example, almost always to be found around the Frog Pond in Kubah National Park in Sarawak). I was glad to see it; after all, I'm a bit of a treehugger myself!