Coeliccia doisuthepensis Asahina, 1984

In August 2011, I made a 3-day motorbike trip to Mai Chau (northern Vietnam, 150 km east of Hanoi), in Hoa Binh Province - that borders the Laotian Province of Hua Phan.

As I was searching a way to enter Pu Luong Natural Reserve, an area of outstanding beauty, I noticed a forest streamlet on the right of the road, at an elevation of about 1,100 m. After 10 minutes exploring the place, I bumped into a male Coeliccia resting on a leaf, 50 cm above the water. I knew it was a new species for me straight away due to the 3 pairs of blue markings on the synthorax dorsum. Later, I spotted 2 or 3 other males. I didn't get to see any females.

Almost certain it was an interesting species (I mean : not only interesting for me, the beginner!), I decided, exceptionally, to collect voucher specimens that were passed later to Dô Manh Cuong. Searching the web once home (not the best ID method, I know...), I identified it as Coeliccia doisuthepensis on the basis of color pattern and markings. One week later, the ID was confirmed by Dô Manh Cuong and R.A. Dow after examination of the caudal appendages and penile organ (a much better method!).

This is Vietnam's first record of this species. The country list of Coeliccia gets longer almost every year (around 14-15 species currently), with the discovery of species new to science or already known in neighboring countries (China, Laos, Thailand…).

Male synthorax bears 3 pairs of pale azure stripes on the front : one anterior pair close to the dorsal carina, another upper but smaller pair ; the third one, on the anterior border of mesepimeron close to the humeral suture, is reduced to 2 narrow lines.

Caudal appendages dull yellowish. In the superiors, the ventral spine is situated rather distally with a sharp spine directed inwardly.

Lateral view

Dorso-lateral view

The penile organ is of curious shape, ending in a horned head and without any filament at all.

Penile organ
(left : sketch of Syoziro Asahina in A list of Odonata from Thailand. Part VI. Platycnemididae - Genus Coeliccia)

Coeliccia doisuthepensis is known in northern Thailand (Chiang Mai and Chiang Rai), Laos and now northern Vietnam, and is likely to occur in Myanmar and southern China.

I found it along a slow-flowing shady streamlet (low gradient, 50 cm wide) running through disturbed secondary growth montane forest in karst terrain. The area was grazing by buffaloes and over-exploited by local people - many hamlets around.
Not really the kind of place particularly promising for Odonata!

(Nota : photos of caudal appendages and penile organ by Dô Manh Cuong, from the specimens collected at Mai Chau).

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