Return Trip To Huu Liên

A nice natural lake enclosed on two sides by karst mountains. 

Last week, I returned to Huu Liên NR in the hope of finding something new for my personal records. So another 220 bum-numbing kilometres on my motorcycle! I arrived at 7.30 a.m. and it was already sunny with a lot common species buzzing around. 

My first disappointment was the lack of Atrocalopteryx sp. nov. on show at the same stream where I saw it the previous week. Bad timing? Bad eyesight? I don't know. But Tom Kompier spotted one male and took pictures before I arrived. So maybe bad eyesight! 

The sun was shining - not a cloud in the sky. This ensured that there was lots of odonata activity. Among Anisoptera, only Libellulids were sighted. The exception was a large male Gomphid with an arched abdomen, white superior appendages and very long S7 or S8**, unfortunately out of range of the camera. He vanished as quickly as he appeared. The 2 other groups well represented were Caloptera (Cholorocyphids, Calopterygids, Euphaeids) and Coenagrionids. 

The highlight - and novelty for me - was Libellago lineata, a beautiful black and yellow Cholorocyphid absent from my habitual odonata hunting grounds around Hanoi. Maybe it prefers karst streams, I don’t know – but it has certainly good reasons not to be there. What is surprising is that this species has also not been recorded at Xuan Son National Park, this well named “paradise for Caloptera”, despite quite similar habitats. 
Northern Vietnam/southern China represent the northern limit of the range of this Indo-Malayan species, that might explain a somewhat patchy distribution/scarcity there.

In the same stream there were also many Heliocypha biforata, another scarce species in “my area”. 

I had 3 sightings of Atrocalopteryx atrocyana at 3 different places, including a sluggish river bordering at one bank paddy fields but heavily tree-lined at the other one. I also glimpsed the female but couldn’t approach her (arghhhh !...). Her wings are completely brown without white pseudopterostigma – unlike Calopteryx coomani and Atrocalopteryx sp. nov. 

I also looked for new locations, ahead of the next dragonfly season, a time-consuming work. In this karst topography, there are few surface streams. Most of them are situated in large valleys where soils are deeper, but these areas are used as much as possible for agricultural purposes. At Huu Liên, good streams for Odonata are the ones winding around rocky hills, with well tree-lined/vegetated banks and limited agricultural activities around.

I used Google Earth (fantastic resource!) and information from local people. “Hi! I am searching streams in forest. Do you know a place somewhere around here? “. “A stream?! Do you want to take a bath?!”.....; “Are you searching gold?!”...

Gold?!.... well not really, but - flying - jewels, YES! 

This exploration delivered only meagre results… but close contact with local people - apparently foreigners are scarce in the area. They understood that I was there for nature observation and only for that, that is exactly what I wanted. I also bought different things at different shops. I think that ecotourism (du lịch sinh thái in Vietnamese) can provide local communities with motivation to maintain and protect forests and wildlife.  When local people get income from us, “ecotourists”, they are far less likely to destroy the natural resources through unsustainable exploitation. 

What I saw during 2 one-day trips: 

Heliocypha perforata (few) 
Heliocypha biforata (many at one place) 
Libellago lineata (many at one place) 
Atrocalopteryx atrocyana (4-5 ♂ +1 ♀)  
Atrocalopteryx sp. nov.* (2 ♂) 
Neurobasis chinensis 
Vestalaria miao (abundant at one place) 
Vestalis gracilis 
Euphaea masoni 
Agriocnemis femina 
Agriocnemis pygmaea 
Mortonagrion aborense* (1 ♂) 
Ischnura senegalensis 
Pseudagrion rubriceps* 
Pseudagrion pruinosum 
Paracercion calamorum* 
Copera ciliata 
Copera marginipes 
Copera vittata 
Prodasineura autumnalis 
Brachythemis contaminata 
Crocothemis servilia 
Diplacodes trivialis 
Neurothemis fulvia*
Onychothemis testacea (1 ♂) 
Orthetrum glaucum 
Orthetrum pruinosum 
Orthetrum sabina 
Palpopleura sexmaculata 
Pantala flavescens 
Trithemis aurora 
Trithemis festiva 
Zygonyx iris 
Unidentified large ♂ Gomphid ** 

* not reported in the “List of odonata from Huu Lien Natural Reserve. Phan Quoc Tuan & Do Manh Cuong”, 2011 (?). The authors listed 64 species.

**subsequently identified as Labrogomphus torvus, new for Vietnam. In fact the markedly elongate abdominal segment was S9 and not S7 or S8 as I previously thought in the field.

 Total: 33 species, not bad for a month of November - and little survey effort at still water habitats.

But Tom found much more species than me. Have a look at odonatavietnam.blogspot.com - he will post soon. Poor eyesight…, this seems to be confirmed :(

So, all in all, it was a pretty good odonata hunting session, with many photo opportunities. I hope to return there at least on time before the bleak season - there are some more goodies there to be seen.

My best photos of these two 1-day trips:
Male Trithemis festiva

Pseudagrion rubriceps, male, fairly common in grassy banks of sluggish streams.

Easily distinguished by the brilliant orange face, from which it derives its name, and which is very conspicuous, even when the insect is on the wing. 

Copera vittata. 
With his yellow legs, this male looks very similar to C. marginipes, but he can be easily told apart by his caudal appendages: somewhat pointed, superiors half the length of inferiors.

Agriocnemis pygmaea in copula, note inf. appendages shorter that sup.

Agriocnemis femina in copula, note inf. appendages longer that sup.

Prodasineura autumnalis, pair in tandem

Ischnura senegalensis, copula with an immature female... this would be deemed illegal in the human world!
Orthetrum sabina.
A VERY common species as everyone knows, but copula are generally hard to approach.

 Male Paracercion calamorum, heavily pruinosed on the synthorax. 

 Stunning amber colored eyes.

Paracercion calamorum, immature male.

Male Atrocalopteryx atrocyana 

Close-up showing the peculiar color pattern of the synthorax.

Sluggish river where I photographed the male Atrocalopteryx atrocyana above (at the well-vegetated bank on the right) and many common Coenagrionids (grassed bank on the left).

Male Libellago lineata.

Another one.

Close-up showing the blue-black metallic “snout”.

Libellago lineata, immature male : abdomen not yet marked with bright citron yellow, 
apices of fore-wings not tipped with black.

A pair of Libellago lineata males face each other in - prolonged - agonistic flight.

Female Libellago lineata 

Female Libellago lineata ovipositing - a tiny fish admire the show!

Male Heliocypha biforata.

Female Heliocypha biforata.

Close-up on head.
The head of Chlorocyphidae damselflies bears a unique upturned snout, or rhinarium, 
which projects far beyond the rather close-set eyes.

Male Heliocypha biforata swinging back and forth in a semicircle around an ovipositing female, displaying his wings and flashing his bright white pruinescent tibia. 

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