Sunday, July 17, 2011

131. Rhyothemis obsolescens (Kirby, 1889)

Number: 131
Family: Libellulidae
Genus: Rhyothemis
Species: Rhyothemis obsolescens
Common Name(s): Variegated Plain Skimmer, Dusky Flutterer, Bronze Flutterer
Thai name(s): แมลงปอบ้านไร่ลายเลือน, แมลงปอบ้านไร่ขีดใส, แมลงปอบ้านปีกลายเลือน
Habitat: Exposed upland rivers
Province(s) sighted: Khao Yai NP (Nakhorn Ratchasima)
Sightings (by me): Uncommon
In flight (that I have seen): June-July (longer, I'm sure)

I have just returned from a 2-day trip to Khao Yai Nationl Park. I visited there for the first time, back in April and it was rather quiet, although I did manage to spot one or two new species. This time, however, I faired rather better. Torrential rain, armies of hungry leeches, heavily swollen rivers and inaccessible areas I had previously visited, didn't put me off (though my girlfriend stayed in the rented car most of the time). And it was worth it. I managed to spot a few more specimens, as well as a lot of non-odonata related things and I had a great time. 

I had been driving around Khao Yai National Park all day and right at the death, I noticed a slow-moving, but swollen river about 900 metres up or so. I chanced my arm and drove towards it. I then noticed it was part of a campsite I hadn't even noticed before. There was a beautiful river that ran though it, shrouded by tall, large lilly pads. I saw a few species and decided I needed a full day there and so planned to camp there with my girlfriend in the next few weeks. As I walked back, I noticed something that looked a little like Neurothemis fulvia. Then I realised... it was a species I had been after for a long time, Rhyothemis obsolescens. I followed the male for long periods, trying to get close to it, but it fluttered further along the lilly pads every time. I followed it about 40 metres downstream and then noticed that there were a few more specimens. Almost waist-deep in mud, I managed to get close enough to get a few half-decent photos, much to the amusement of the camping Thais, and the embarrassment of my girlfriend. So, there you have it... all 5 species in the Rhyothemis genus! I couldn't be happier.


Since then, I have returned and found both male and female!

The male
From a distance, the male looks much more boring than its cousins. However, on closer inspection, its a vivid bronze with lots of dazzling variants in colour and patterns on its wings. It really is a truly magnificent creature.




In the hand...
I managed to capture a young male. As you can see, they are small, but no less beautiful.


The female...
Early one morning, I ventured out to the river while my girlfriend was still in the tent. I was glad that I did, as I saw not one, but two females! As with all species in the genus, the females usually hide far away from the water's edge.


The female is identical to the male, except its abdomen is more robust. This one has a damaged forewing.



Here's another female, which I also managed to capture with my little net (it's really handy!)





Now in the hand...
This shows just how similar the female is to the male.


4 comments:

  1. Could you kindly let it known on the terroitory of which province you managed to photograph this splendid species? Obviously a new provincial record, for it was recorded far from that area. But the Natural Park resides in four provinces altogether...

    Oleg Kosterin (aka lj-user multifidum, unfortunately, my blog is mostly in Russian...)

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  2. Could you be so kind to possibly drop me a message to kosterin@bionet.nsc.ru , for me to be able to consult you on some Thai odonata matter via E-mail, if you don't mind?

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  3. Hi Oleg,many thanks for the message. I have left a message on your site and emailed you also.

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  4. Congrats, Dennis! Did you see Dysphaea gloriosa there?
    I also got what I want to see!

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