142: Gynacantha phaeomeria (Lieftinck, 1960)

Number: 142 / Family: Aeschnidae / Genus:  Gynacantha 

Species:  Gynacantha phaeomeria / Dark-thighed Dusthawker*

Habitat: Forested Areas Along Rivers

Province(s) sighted: Kalasin, Loei

Sightings: Rare / In flight (that I have seen): June-September

Species easily confused with: All Gynacantha species

*As it doesn't have a common name, I decided upon 'Dark-thighed' relating to 'phaeomeria' meaning 'dark' and one feature of dark thighs/legs, as well as Gynacantha species being known as 'Duskhawkers'.

It was a weekend of agony and ecstasy at Phu Rua National Park and environs. Heavy rain, heavy mist, bad judgement on locations and a lot of driving, nearly put paid to my weekend trip.

After a sleepless night, I set off from Khon Kaen at 1am and arrived in Phu Rua at around 5.30 am with a few stops here and there. After a few bad choices on ponds (maybe it was too early in the morning), I tried my luck at the national park. Closed. Upon asking a man with a dog, who said "It's closed in the rainy season", I drove to another waterfall called Namtok Pla Ba, not too far away. It was part of an enormous river and the water was belting through at an unbelievable pace. The waterfall was low down and inaccessible, as too was most of the river. Back on the road. I saw a small waterfall called Song Khon Waterfall close by and chanced my arm. It was a stream. Good. It was in good forested area and I started searching. My last 3 trips proved fruitless, in terms of new species. After 6 hours of searching, this too seemed to be the same with only common species showing. I did see a female Gomphidae, but as quickly as it appeared, it disappeared. I searched for another specimen, but it was all in vain. Right at the exit of the trail, I noticed a large Aeschnidae move under heavy tree canopy. I edged forward and managed to get a few good photos. It turns out that it IS a new species... Gynacantha phaeomeria. A rare specimen indeed and a new provincial record (I think). So everything is good in the world, once more! Since then, I was fortunate enough to spot a fully mature male at Phu Phan National Park in Kalasin, back in 2018.

The Male

The fully-coloured male is simply beautiful as is easily recognisable with its blue head, green thorax and dark abdomen. The other thing of note is the white part of the anal appendages.

 

The 'Young' male
Unlike the fully mature male, the juvenile male looks like many Gynacantha species at this stage and relies on the shape and colour of the appendages, in this case, the prominent white part.

Many, many thanks to Noppadon Makbun and Mapor for the ID and useful information/papers on the species. Your help is vital in my identification as I am useless!

So, all-in-all, it turned out to be a good trip. Next trip... Chayaphum, Nam Nao then Tak (hopefully).