Saying good-bye, a last visit to Xuan Son National Park

After 4 years of oding in Vietnam, I will be leaving. This blog will continue, because there is still a lot to publish. I have just been too busy trying to clean up some remaining issues. There simply was not enough time to write entries. Articles are the priority and even there I am behind. Not sure how many species the tally is, after 4 years. Probably around 440 species, but many first need a formal description. And then there is so much out there still to discover.

This spring and summer has been awful for dragonflies. It has just been cloudy and rainy. Some of the puzzles I wanted to solve therefore remain unsolved for now. But at least Sunday 23 July was a good and sunny day, even if I got soaked in the morning. The upside: only one leech lodged on my stomach.

Xuan Son has been wonderful, although the forest is being opened up by road building. I hope that will not lead to further incursions. The trees still stand and the stream remain good. Not sure how many species I actually saw there, somewhere in the range of 125-135 species. With several new species described and several more on the way. So, with the promise of some sun, this is where I went for my very last outing.

And to my huge surprise I ran not into 1, not 2, but 3 species I had not recorded there before. The first was a male Orthetrum melania superbum, a subspecies of O. melania described, and also only recorded, from Yen Bai. A large and conspicuous dragonfly that apparently tolerates abysmal conditions (puddles with muddy, water buffalo dung infested, water), but is nevertheless hardly ever seen. A single male attended a small pond. Fantastic.

This remains one of the most beautiful Orthetrum species I have seen 

By the early afternoon I wanted a change of scenery and drove to a nearby hill in the forest and noticed a dragonfly seemingly ovipositing on the wet concrete road. I got out and caught it and was very surprised to see it was a male, so why was it dipping its body in the wetness of the concrete? And it was a Chlorogomphus, in fact it was C. auratus, which I had never recorded in the park before. I guess I focus too much on the one fantastic stream, but ignore trickles on other mountains.

What is splendid discovery, Chlorogomphus auratus

Further afield still I wanted t check the area on the other side of the central hamlet and stopped by a small stream. A tiny trail ran next to it and I went in to see what it had to offer. And bumped into a small, Coeliccia pyriformis-sized, Coeliccia with large pale blue dorsal markings, a little like larger C. uenoi, but more rounded, and much like the even larger species we are currently describing from Ba Be. Indeed, under the microscope it is clearly closely related to that species, with similar genital ligula, similar appendages (although details differ), but obviously different thorax pattern and abdomen pattern (apart from the total insect being smaller than the abdomen of the Ba Be species alone, which is very robust).

To make sure it was not just aberrant I searched high and low and eventually, in a rather different location, was able to locate a second male, which was exactly like the first. How wonderful, to wrap up Vietnam with a new species of Coeliccia (coincidentally the 9th species of the genus occurring in Xuan Son, amazing).

Wonderful Coeliccia spec. nov. 

Close up of the thorax

So, back to the Netherlands and time to write up in earnest!

Orthetrum internum headaches

Last Thursday I was in Sa Pa and as usual this time of the year Orthetrum internum was already out in good numbers. Wen-Chi Yeh had responded to my posting of the species in 2014, but I had overlooked the significance of his comment. Basically he said that my photos looked different from what he was used to for O. internum. I had noticed that lack of pruinosity on the  dorsal side of the thorax, but in my posting mentioned this as one of the characteristics of O. internum. How wrong can you be?

Yesterday I visited Pia Oac in Cao Bang and ran into O. internum is several places. This in itself is strange, because I had never seen it there before. But even more strange was the fact that they were clearly pruinose and much more black-and-yellow. These were true O. internum! But if so, then what is the species in Sa Pa?

Structurally the two are identical. I am not sure if there are structural differences visible to us between O. internum and O. japonicum. These two were considered subspecies of O. japonicum in the past, until DNA sequencing made it clear they were in fact separate species. So, the lack of structural differences does not necessarily mean that the Sa Pa species is O. internum, nor does it support the other option, of course. But in coloration it is very different. The labium and labrum are pale orange, not black. The frons lacks black edges dorsally. The venter is not nearly as black, with the hamulus pale brown with only the tooth darker brown, but it is black-and-white in O. internum. And the thorax ground colour is black or dark brown in O. internum, with clear yellow on the prothorax (especially posterior lobe). In the Sa Pa species the ground colour if brown with pale markings, and there is no yellow on the prothorax, just pale areas. And most interestingly, there never is any pruinosity on the dorsum of the thorax!

From Sa Pa, note orange labium and labrum, brown color of thorax, no pruinosity, pale thoracic markings. Photo taken in 2014

Last Thursday. Note some characteristics. 

But this is a very black O. internum. Note also black labium and labrum, black on top of frons, pruinosity on the thorax, from Pia Oac

In dorsal view

A slightly less black male from Pia Oac. Note also the clarity and extent of the yellow markings on the thorax.

Note the yellow posterior lobe of the prothorax.

Trip to Nam Bung (Yen Bai) - a superb surprise and a second Anotogaster*

*Adjusted on June 1, 2016. This subspecies now published as Orthetrum melania superbum.

July 11 I drove all the way to Nam Bung along the QL32 (in Yen Bai Province) in search of an enigma large Periaeschna species, of which I caught a female two weeks back. But I failed to see it again. I spent the beautiful day along a stream that runs through forest and a canyon, the same place where I had seen the Periaeschna.

The trail through the forest had some puddles and it was here that I spotted a large pale-blue Orthetrum with pale appendages, a dark face, and a black dorsum to the thorax with very prominent and clear antehumeral stripes. The wingtips had a darker crescent and the wing bases had a prominent blue-and-black basal patch. I was pretty convinced that by now the genus Orthetrum was not going to present surprises, but here I was faced with what was obvious a new species for Vietnam.

I collected a single male of the 4 males present at the puddles. It is very weird. These puddles were dirty, with buffalo crap and mud, nothing special. If you consider this, why on earth would this species be rare? Also interesting, Orthetrum triangulare was omnipresent (it is a very common species in this area), and also all around, but not at these few puddles. Clearly it can not compete with this species (in fact the abdomen of O. triangulare is 30mm, but of the present species 37mm, so it is much larger).

From the shape of the appendages, the coloration (face, wing base and tip, abdomen, thorax (but not the dorsum) I can only conclude this is Orthetrum melania. This species was long considered to be a subspecies of O. triangulare, although that is no longer the case and the co-exist in the south of China. Indeed, structurally the caudal appendages and sex apparatus look similar unless you look carefully. Originally this species was thought to be restricted to Japan, but it is now known to have a much larger range. O. melania has also been found in Guangdong, Guangxi and Yunnan. Therefore it is maybe not surprising it also occurs in Vietnam.

There are however a few aspects that indicate that this may be an (unknown) subspecies. The specimen is right at the top of the range for Japanese specimens, with abdomen 37mm. The median space in the hindwing is clear, but integral part of the basal patch in the Japanese specimens. The basal patch is also smaller, not covering the base of the anal loop. But most prominently, the dorsum of the thorax has no pruinosity. It is solid black with clearly demarcated antehumeral stripes that are not pruinose, but truly blue in color. These antehumerals are surprising, because they are absent in the true O. melania, which has a unicolored pale dorsum as immature, that gets covered in pruinosity like the rest of the thorax. Most Japanese specimens have all black appendages, but some have paler tips of varying extent. As can be seen in the photos of the Yen Bai specimens there is some variety there too, from all pale to pale in the apical halve. Nevertheless, the overlap in characteristics makes it unlikely this is a completely different species. I am curious to hear what specimens in the south of China look like. If they are the same as in Japan the present specimens are even more remarkable. I have not been able to find any similar species on the web.

Another surprise was Anotogaster klossi. I have seen A. gigantica in the same general area, but A. klossi only at Pia Oac. Interestingly, it passed over the same track and puddles where I found O. melania.

Let's get this out of the way. Anotogaster klossi, with characteristic reddish colour on abdomen, yellow mandible bases and long superior appendages in which no obvious tooth visible halfway. 

To start the argument: scan of Orthetrum triangulare (top) and O. melania (bottom). The size difference is obvious.

The first male O. melania I noticed. This specimen has completely pale appendages.

The same male in dorsal view. 

The same male in hand. The dark face clearly visible. But what is especially eye-catching is the dorsal pattern. Although the lateral grey is a powdery substance that is easily scratched, the antehumeral stripes (or maybe dorsal stripes is better) are not the result of powder. They contrast very strongly with the solid black remainder.

Note the lack of colour in the median space

Another male, with mostly black appendages with only pale apices.

Appendages in ventral view

In dorsal view

And in lateral view

The hamulus and lamina in lateral view

12 April, Melinh Field Station

April 12 was a beautiful day and I headed to Tam Dao to check raptor migration. Nothing flew, so very disappointing. Apart from a lone Chlorogomphus that is, exciting to know they are around already. But without birds, I decided to try Melinh. In a recent publication, Natalia von Ellenrieder et al. mention some interesting species from this area, but I had never been there. So I tried to go and stumbled onto the place without much difficulty. It has basically one major stream that runs through secondary forest and I followed it for quite a bit. Euphaea guerini was probably the commonest species. It is not all that common really, with Xuan Son providing good numbers, but elsewhere it is rare. Here is was common, followed by Mnais mneme, another nice species. And yet another reminder of Xuan Son was Prodasineura croconota, which I know also from Huu Lien. The commonest dragon was Orthetrum sabina, and for once I took some pictures of it. Other interesting species were Protosticta "grandis", a single female, Orolestes selysi, and Mortonagrion aborense, although that species by now is known to occur widely. The only gomphid was Ictinigomphus pertinax. Here are a few photos.

Brachydiplax chalybea flavovittata, a single male on a grassy pond

Handsome Prodasineura croconota, now also known to be widespread

Not a good picture, but it will do, I guess. Mnais mneme, orange-winged male

And because it was too common to ignore: male Orthetrum sabina

It's a male's world (but it would be nothing without females)

Hanging around Pia Oac on April 4 and 5 I bumped into several interesting females that I would like to share here. Plus one interesting copula.

This here is the female of Mnais andersoni, by virtue of its association with a bundle of males

This is a copula of Ischnura carpentieri. The andromorph female it not common at all

Female Trithemis festiva, much more difficult to find than the male

Ovipositing female Anax nigrofasciatus

A different female A. nigrofasciatus, caught hunting over the road on the mountain

Female of Orthetrum triangulare with less clearly marked thorax compared to O. glaucum and dark tip to abdomen

Some additional species at Huu Lien from April 21

The two Copera species of Huu Lien and the one Pseudocopera were already common and easily found. Here are the males of P. ciliata and C. marginipes in their full glory.

Pseudocopera ciliata is the easy one, large, and white when mature

Here a male Copera marginipes with its simple, but large superior appendages

A somewhat messier C. marginipes. C. vittata normally has much less white on the last segments.

A remarkable and large species was Orolestes selysi. The dark-winged form and the hyaline form occurred side by side.

A fantastic dark-winged specimen of Orolestes selysi

The somewhat less striking, sorry to say, hyaline version.

I also had the opportunity to take a better look at some immature Orthetrum glaucum.

First, a female Orthetrum glaucum.

A fresh, still less pronounced, female

The interesting immature male. The striking pattern is later completely obscured by pruinosity.

Orthetrum internum

Orthetrum internum was described by McLachlan in 1894. In Vietnam is was found by Do Manh Cuong in Vinh Phuc Province, at Tam Dao, but between 14 and 16 April we found this early flying species in Lai Chau, Lao Cai and Yen Bai Provinces as a common species. Likely it is widespread in Northern Vietnam, maybe overlooked because it flies so early. It differs from closely related O. japonicum for instance by the lack of pruinosity on the dorsum of the thorax. Here are a few photos  from Phan Xi Pang and surroundings.

The female Orthetrum internum hovering at ovipositing place over very shallow puddles

A male O. internum

The male hover-guarding the ovipositing female

Sapa, 14-16 April

To continue the saga of Sapa, we arrived late on Sunday 13th after a grueling drive, persuaded by my Papago! to drive a different route, not as I planned along QL 32, but first along QL 70, where we eventually ran into a traffic jam and had to U-turn, drive back for an hour and then followed TL 151, equally disastrous, as it was no more than a off road dirt track ruined by working traffic for the highway being built. But we made it. In Sapa we noticed great dragonfly spots, but did not specifically explore them, as this was a birding trip. However, the swampy field along the trail to Love Waterfall was very productive and birding the lower areas of Phan Xi Pang mountain was also great, irrespective of the time of the year (early) although diversity was still low.

I will need some time to sort everything out, but this is the information I can share right now. Any suggestions on the IDs are very welcome. The streams were still mostly empty, but the pools and swampy fields had interesting species. Orthetrum glaucum, O. pruinosum, O. triangulare and O. sabina were to be expected, but O. internum was the commonest species by far. I had not seen it before in Vietnam. The presence of Anax nigrofasciatus was a nice surprise, with 2 males at the marsh of Love Waterfall and another somewhere over a pond. A freshly emerged, but somewhat damaged Anotogaster male was also a wonderful find on Phan Xi Pang. And Libellula melli was yet another species I had not expected. This cousin of the Eurasian L. depressa occurs in Southern China but to my knowledge is new for Vietnam.

Damselflies were also very interesting, although I encountered only a few. A Megalestes species was found emerging at various locations and once a mature female was seen, but escaped before it good be photographed. Common in a variety of habitats was a species that seems to be a Mesopodagrion species, and as it does not look like M. tibetanum, it could be M. yachowensis. To be continued. Another species seen only once is also an unknown, suggestions are welcome. This was a beautiful species similar in size to the Mesopodagrion and interacting with it in the forest. I am at a loss for now. And the last damsel found was Ceriagrion fallax. It was common at one particular stream near Sapa town.

Let's start with the completely unknown, suggestions welcome!

The same damsel, detail of thorax

The same damsel, lateral view of appendages

Anax nigrofasciatus, male

Ceriagrion fallax, male

Orthetrum internum, male

Megalestes spec, work in progress, female

Very cool Mesopodagrion species, male

Mesopodagrion species in tandem

Libellula melli, male, new for Vietnam

The unfortunate Anotogaster male, something went wrong during emergence