Some Xuân Son goodies in the rain

Misty mountains at Xuân Son, after the rain

Back to Xuân Son National Park on July 12th. A typical rainy season day with heat, dark clouds, sun and of course (torrential) rain. At this season, depending of the day, you can have more sun and less rain, or vice versa. A completely unpredictable weather.
The morning was quite sunny but the afternoon the heavens opened and that put paid to my day. The long way back to Hanoi was an epic motorcycle journey...
Below some shots taken during this (too short) session :

Ceriagrion azureum, copula

Found at an open pond in a village. A new species for my personal records. 

In mountain areas I usually ignore open habitats in favour of forest habitats, that's why I overlooked it. 
Under these latitudes, there are often some "bad" bugs (parasitic worms/leeches) in standing water so I always avoid to submerge my butt in ponds. But this time the temptation was too strong!

Matrona taoi, male, well hidden in the forest
A newly (2011) described species, hitherto known from Xuân Son (type locality) and a site in central Vietnam (Quang Binh Province). A Matrona species with metallic green abdomen and brown-reddish wings, lacking any milky coloured reticulation at the wing bases of the male (unlike Matrona basilaris for example).

It was the only Matrona taoi I saw during this short trip. More easy to find in autumn, after the rainy season (October, November & December).

Archineura hetaerinoides, male

That smells like the end of the season for this species, more abundant in April, May and June

Chlorogomphus sachiyoae, male (identified afer in-hand examination, of course)
A typical view of a male Chlorogomphus patrolling up and down a shallow rocky stream, with a slow flight, few dozens of centimeters above water. Found this guy some kilometers before Xuân Son, in a small, incised valley (depth of 15m or so) surrounded by... manioc fields!  Other interesting species there included Coeliccia sasamotoi and Cryptophaea vietnamensis. I have already noticed that interesting forest species can still maintain in very degraded habitats if woody riparian corridors have been conserved.

Euphaea masoni, male & female

Euphaea masoni, male
Note the coppery sheen on upper-side of hind wings (not often visible, generally wings appear all dark). Its close but less common congener E. guerini show an obvious greenish sheen there (see photo below), visible even in bad light conditions; but closed winged of both species show a blue-green metallic sheen. Anyway, the easiest way to separate the two species is by taking a look at the ventral base of S9, where E. guerini has a tuft of long hairs.

Euphaea guerini, male
Note the hairs at the ventral base of S9 

Euphaea decorata, male
A widespread and common species in northern Vietnam and southern China, occurring in both lowland and mountain streams.

A newly emerged male Euphaea decorata

Euphaea ochracea, male
Seems scarce at Xuân Son - only one male spotted. 
Three other Euphaea species are found at Xuân Son (masoni, guerini and decorata), all common.

Lamelligomphus formosanus, male 
Like its congeners, this species is a hovering champion, so it should be easy - in theory - to photograph it in flight. But this little fellow is skittish and quite difficult to approach. 

Lamelligomphus formosanus, female at an oviposition spot

Prodasineura croconota, male

Back To Field Work At Huu Liên

My first 'proper' trip of the season: Huu Liên Nature Reserve (110 km north from Hanoi). Very late 1st trip I must confess... Upon my return to this dragonfly haven for the first time in 4,5 months, I expected to find new records to add to my personal list – and I was not disappointed.

The first place I visited was a small pond. As I made my way gingerly across its marshy margins, I came across a small Gomphid perched on scrubs. I managed to get a few record shots before it shot off rapidly... I searched half an hour, circling the pond several times, and finally find another but perched too high for me to net. It was a Trigomphus sp., one of the 'new' (new for Vietnam, at least) Gomphids recently found and identified by Tom.

After this very good beginning, I tried my luck at a nearby slow moving stream, a quite open one but with some scrubby sections. I flushed there a large, pale grey flatwing damselfly, with striking reddish pink last abdominal segments. I instantly recognized Philosina buchi, a  Megapodagrionid damselfly new for Vietnam, just discovered 2 days before! I immediately identified it because I checked some photos on the web before the trip, thanks to Tom’s SMS informing me about his discovery. According to the IUCN red list information, it is known from south-western and southern China including Fujian and Guangdong, Guangxi and Sichuan. A new species for me, and a gorgeous one! I was so happy.

Later I spotted through the binoculars some perched - but skittish - Nihonogomphus sp. and a solitary male Gomphidia abbotti basking in glorious sunshine. Though difficult to get anywhere near, I eventually got some okish-shots of the latter.

The Chlorocyphids Rhinocypha perforata, R. biforata, Libellago lineata were all on wing but in small numbers compare to last November. Few Calopterygids, with the exception of some Vestalis gracilis and the successful Neurobasis chinensis. Bumped also into some males Orolestes selysi, always a nice sight.

The rest of the day I saw plenty of odonates flitting around, but most of them common. The most interesting were Ceriagrion nipponicum (Huu Liên is its only known locality in Vietnam), an Asiagomphus sp. never recorded in Vietnam and possibly new to science (1 male collected) and a copula of the enigma Pseudagrion sp. nov. (or maybe Paracercion, let's wait and see for the results of the DNA test) discovered last year by Tom. 

Here's are some of my best photos of the day :

immature male Trigomphus sp. (thoracic/abdominal markings yellow when fully mature)

male Philosina buchi

What a privilege to spot a beautiful creature like this!

Gomphidia abbotti – stunning beast!

 male Vestalis gracilis

 male Ceriagrion nipponicum

                    Copula of the 'Pseudagrion' sp. nov. found in Huu Lien last year. 

                                        So far only recorded from a single reservoir.

Close-up on the female. Note the same distinctive marking along the interpleural suture 
as in the male and the double light line along the humeral suture.

 

 copula of Copera ciliata

a smart male Copera ciliata

 male Libellago lineata
This species has a long flight season; at Huu Liên from early spring till December.

male Rhinocypha biforata

male Orolestes selysi patch-winged form – a personal favorite.

male Zygonyx iris

copula of Orthetrum pruinosum. Always hard to get near.

 female Urothemis signata

Asiagomphus sp. 

 New for the country, probably yet to be described. For the discussion concerning its identity, visit Tom’s blog.