Tuesday, 28 April 2015

Sinictinogomphus clavatus - both sexes

Sinictinogomphus clavatus is a common and widespread species in Vietnam, that occurs at ponds, reservoirs and slow streams. In can be found even in Hanoi, irrespective of the water quality. Clearly it is a very tolerant species. It seems to appear before Ictinogomphus pertinax, from which it can be easily separated by its yellow tibia and yellow-centered flanges. On April 5 I encountered it already on various locations in Bac Kan and Cao Bang Provinces. (The last record of last year was on September 6.) On April 5 I caught a tandem in flight trying to find a place to oviposit at a freshly inundated rice field in the mountains. Apparently by then they were already fully mature. As I do not have that many photos of females, I reproduce both the male and female here.

Female of Sinictinogomphus clavatus, very similar to the male. Of course no anal triangle in the hindwing and different appendages.

The male, somewhat reduced yellow on the abdomen. but as usual in gomphids rather similar to the female. Note the extended penile organ. I apologize for the coitus interruptus. Although released after I took the photos, I doubt they resumed.

Hylaeothemis clementia - almost overlooked

Sunday April 26 I drove very early to Yen Bai Province along the QL32 for what was supposed to be a sunny few days in Yen Bai and Sa Pa. It turned out not to be that way at all. But while working my way up along the road after Nam Bung in Van Chan commune I checked the trickles and streams crossing the road and on one flushed a teneral small dragonfly. It attracted my attention by the bold yellow-and-black thorax pattern and the abdominal pattern with a large double spot on S7 not unlike Micrathyria species in the neotropics. As I caught it I assumed it was a Tetrathemis species, exactly because of these characteristics. It also seemed to have the black face with yellow band across. So I almost released it. But it did not seem right somehow, too large and the wings, although amber at the bases, where not amber across the complete inner wing. So I decided to take it along.

Monday evening, after another cloudy day, I had returned home and checking it in the evening noticed the peculiar secondary genitalia. Of course it now also dawned on me that the thorax markings were not right after all. I opened up the volume on Thailand by Asahina and with a strike of good fortune opened it as Hylaeothemis clementia. There it was!

A rarely recorded, but possibly overlooked, dragonfly, H. clementia to my knowledge has been recorded once in Vietnam, in Son La Province in 2003 (Sasamoto & Do, in Do & Dang, 2007). Son La is adjacent to Yen Bai Province, and the sight where is was recorded is about 100km away from my site, as the crow flies.

I found my specimen along a small stream with a few puddles in heavily grazed and degraded woodland on a hill side. As it was freshly emerged, this must be within its habitat range.

Fresh male of Hylaeothemis clementia, easily overlooked!
But both the central dorsal line and the lines over the humeral suture are different from T. platyptera.
The facial pattern is reminiscent of T. platyptera, which similarly has anteclypeus, postclypeus and antefrons yellow.
The hamulus is a clear give-away though, very different

Tuesday, 21 April 2015

Two interesting females with their males

On April 5 I flushed a fresh damsel from a stream in Cao Bang Province at the foot of Pia Oac Mountain that upon study through my binoculars appeared to be a female of Sinosticta debra, a species I found first for Vietnam last year in Xuan Son National Park. But it flew off before I could take a picture. Luckily on April 18 I saw another female briefly in Xuan Son and this time managed to take a quick ID shot. The same day I also managed some photos of the male. Probably, as this is an early species, the next time I visit they will already have receded in the mists of time.

On April 19, this time in Huu Lien, I saw several Gomphidia abbotti, a not so common, but widespread, species in at least the north of Vietnam. But I also caught a female, something I had not seen previously.

Gomphidia abbotti, male
And Gomphidia abbotti, female

The vulvar lamina of the female

And the final segments in lateral view

Something completely different, elegant Sinosticta debra, male

Undoubtedly as elegant, the female, at least a photo

Monday, 20 April 2015

Coeliccia mingxiensis - the 7th Coeliccia for Xuan Son

Coeliccia mingxiensis was found in 2009 by Do Manh Cuong in Tam Dao near the Belvedere Resort. That was the first record for Vietnam after its description in 2006 from Fujian, China. Last year I also found it in Tay Thien, in the same mountain range, which I considered good fortune, as the stream near Belvedere Resort is under a lot of pressure. But even after many visits I had never seen it at Xuan Son. That is, until last Saturday, when unexpectedly I ran into a single male of this spring species. The same stretch of forest holds also C. scutellum, C. cyanomelas, C. uenoi (well, actually, that is a little further away), C. poungyi, C. sasamotoi and C. pyriformis. Quite amazing! Apparently this beautiful species is more widespread.

Male Coeliccia mingxiensis, unmistakable.

Close-up of the hooked dorsal stripes and orange lateral stripe.

Sunday, 19 April 2015

Fukienogomphus prometheus - new for Vietnam! Not!*

*Haruki Karube commented that he has specimens from Cuc Phuong and Huu Lien and that the species has also been found by Do Manh Cuong, although as far as I know these records are not published.

Today I visited Huu Lien Nature Reserve. It is still good, but for how much longer? The forest trail is now more and more a trail in the open sun, with more and more trees turned into charcoal by the locals. It is a sad affair. But anyway, in one of those open spots a noticed a gomphid perched on a leaf. It relocated, giving me a bit of a fright, but settled close by and I could catch it. In hand it reminded me of Fukienogomphus, a genus I had not yet seen. At home I checked the literature and Sebastien's blog. He has seen representatives of the genus twice in Tam Dao. The first thing I noticed was that Sebastien's specimens were much darker, with almost no yellow on the metepisternum. And the lateral processes on the superior appendages were also larger, the tips of the appendages darker. He had identified his specimens as F. promineus, which is rather larger than the other two known representatives, F. prometheus and F. choifongae. Cuong also recorded F. promineus from Mau Son in May 2010. He identified his specimens on their structural characteristics and size. And he notes that they are different from the Chinese specimens in the almost completely black metepisternum. They were in fact precisely the same as those observed by Sebastien.

My specimen was 61 mm in total length, with abdomen 46 mm (incl appendages) and hindwing 37. A little too large for F. choifongae. The inferior appendages are widely divaricate, way over 90 degrees, which sets it apart from F. choifongae, but my specimen, and in fact also the very dark specimens of Sebastien from Tam Dao, has black metakatepisternum. That should differentiate F. choifongae from the other two (Wilson 2006). Apparently that characteristic is variable (as is the antehumeral spot, missing both in my and in Sebastien's specimens). Based on the shape of the appendages, the posterior hamule and its measurements, I identified my specimen as F. prometheus. This is a common and wide-ranging species is China, and occurs in neighboring Guangdong and Hainan. It should not come as a surprise that it also occurs in Lang Son Province. It is thus the second species in the genus.

Fukienogomphus prometheus, male, with extensively yellow on metepisternum, but black metakatepisternum.

Distinctive appendages in lateral view. Note the square ventral process.
And in dorsal view. Note widely divaricate inferior appendages and small lateral processes of the superiors
Black metakatepisternum and secondary appendages

Saturday, 18 April 2015

Camacinia harterti, verified

On May 31, last year, I walked through the forest in Xuan Son National Park when a large red-and-brown dragonfly flew past with some burned caramel wing bases. I was certain it was the possibly ultra-rare Camacinia harterti, but no photo and indeed just a few seconds, if that, of observation time. Not nearly enough to claim such a mega species. And no matter how I searched, I could not find it again. That is, until today, almost a year later. I walked yet another trail in the forest and passing through a clearing formed by tree fall, I noticed a large dragonfly perched on the tip of a branch. No doubt about it, Camacinia harterti! From its perch it made wide-ranging patrol flights, catching small prey, and returning after 10-15 seconds to its perch, after having swooped around the whole clearing. After a while it changed perches, picking again an exposed dry strong stick, almost vertical, on which to sit. It was quite at ease. I could even touch its wings without it taking offense.
It may well be that this forest species is overlooked. Do Manh Cuong recorded a male in Tam Dao. That record was also in April, on April 14, 2009. This may not be a coincidence. Possibly it is an early species.
Camacinia harterti, male, quite unmistakable

Quite interesting how the yellow of the wings is matched by the more orange S1-3

Not at all deterred by the spikiness of the substrate

Sunday, 12 April 2015

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

Wednesday, 8 April 2015

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

Ceriagrion species of early April in Pia Oac

4 and 5 April I visited Pia Oac and surroundings. Ceriagrion fallax is a common species here and was already abundant around ponds. But I was thrilled to also find Ceriagrion bellona, a species I had previously seen only at Xuan Son. And not only did I see it at the "Trigomphus carus" pond on the slopes of Pia Oac, I also saw it at the weak bridge 10km to the south. Clearly it is not rare in the area. I saw C. auranticum there too, only one male, but more thrilling, because it is less common, even scarce, and extremely beautiful, I saw a great many C. azureum. One could almost say it was abundant on the flooding rice fields. Here are some impressions of all but C. auranticum.

To start with a copula of C. azureum
A male, this specimen with some spots on the thorax, likely some kind of damage.
And the greenish female of C. azureum
Copula of Ceriagrion bellona. Note the yellowish-green eyes and dark dorsum of S9-10 in the male.
Another male C. bellona
And finally, common but pretty Ceriagrion fallax

Tuesday, 7 April 2015

Trigomphus carus - a new species for Vietnam

Saturday April 4 it was an absolutely lovely day and I woke up very early for birdwatching in Pia Oac. When the sun became hot I went to a lower area on the mountain and checked also some streams and a small pool by the roadside. It was here around noon that I noticed a small gomphid perched on a blade of grass over the pool. I was taken aback by it. From a distance its pattern reminded me of Davidius species, but after a quick photo I was able to catch it and in hand quickly concluded it was a Trigomphus species. Only a few minutes after I had taken it another landed on exactly the same blade of grass. Because these are difficult and variable species and because it was a new species to Vietnam for sure, I took this male as well.

There are 14 known species of Trigomphus, although the true number may be smaller, with several synonyms in use. (The 14th is the new species from Vietnam I found last year, which will be described by Karube in an article to be published in May this year*). The particular thorax pattern, shape of appendages and of the genitalia all fit very well Trigomphus carus, a species only known from Fujian in China, as far as I can tell.

This species has the dorsum of the thorax marked by thin "7" shaped stripes and a small antehumeral spot. In fact as is often the case, this character is somewhat variable. One specimen has it, the other does not. Also there is some variation in the lateral thorax pattern. Shape of posterior hamulus is rather distinctive for T. carus and also the somewhat triangular outline of the anterior hamulus is indicative. The inferior appendages, interestingly, curve outward slightly, whereas in most species they curve inward. The match in appendages, anterior and posterior hamulus and penile organ, plus the close match in pattern of the thorax and size (one specimen has abdomen 37 and HM 30mm, the other 36 and HW 29mm), makes identification as Trigomphus carus possible.

* Described as Trigomphus kompieri in the May 2015 issue of Tombo

Trigomphus carus male as found, perched on a leaf 40cm above the water of a small pons
The same male, in hand. Note the anal triangle with 5 cells.
Both males scanned in dorsal view. Note the absence of the antehumeral spots in the top individual, which shows the sometimes limited use as an identification feature.
Both males in lateral view. The bottom individual with slightly less black on the sides of the thorax.
The face of Trigomphus carus, with all-black labrum.
Appendages in dorsal view. Note the lateral process at two-fifths.
Close-up of the right superior appendage in dorsal view.
Lateral view of the appendages. Left side and right side not exactly the same.
Inferior appendages in ventral view. Characteristically slightly curved outwards. The orange bit is poop.

The ventral view of the hamuli. Note the bulging swollen posterior hamuli adorned with a crest-like inward-facing hook.
And lateral view of the hamuli. Here the "hollowed out" triangular anterior hamulus is essential.