Sunday, 25 May 2014

Ba Vi National Park has more to offer

This morning we wandered around Red River Island looking for river breeding gomphids, but we did not find any. Thereafter I drove to Ba Vi to try my luck there. We still have the Drepanosticta enigma to solve. Checking the streams I ran into two new species for my list. Sinorogomphus nasutus is a species I really wanted to see and I am happy I succeeded. Thank you Sebastien for pointing the way! The other species was a Leptogomphus. Haruki Karube showed me the manuscript of his upcoming article for Tombo on Gomphids from Vietnam. In it is also Leptogomphus elegans, which allowed us to identify a Leptogomphid enigma. Sebastien had photos of the appendages of a Leptogomphid that he could not identify, but now we can. I really did not expect to see that same species at Ba Vi. A happy occasion!

Sinorogomphus nasutus, male

Face of male S. nasutus

Lateral view of the appendages of S. nasutus

Dorsal view, normally inferiors would be visible, but S10 bent downwards

Photos in the field failed, so a scan of Leptogomphus elegans, male

The same reason, the same male
Appendages in dorsal view
In lateral view
In ventral view

And the apparatus of S2

Saturday, 24 May 2014

Two supercool additions to my list from Huu Lien

Saturday May 24 I drove to Huu Lien Nature Reserve. In the heat one of my tires blew out while I was parked along the road, presumably. It was quite a thing to replace the tire in the blazing sun, but the day made up for all that.

I had discussed with Sebastien the lack of Rhyothemis species in northern Vietnam. We always only see R. variegata. Nice, but there are other species out there, maybe. Indeed, today I ran into one. And not just once, I saw at least 6 males and 1 female. Rhyothemis plutonia. A marvelous species. I only managed some far away shots, but happy to at least have a record of them.

Rhyothemis plutonium, male

The same male, different pose
The second species I ran into when it was so hot that hardly any dragonflies were out and about. Along the stream in the half open area that once was (not so long ago) solid forest I noticed a massive dragonfly sitting. I took some far away shots before catching it for a few in-hand photos. This was Megalogomphus sommeri. Giant hooktail, what is in a name….

An awesome gomphid, Megalogomphus sommeri, male.

Same male in hand, allowing some close-ups
Appendages in dorsal view
Appendages in ventral view
And finally in lateral view, awesome, giant hooktail
Interesting detail of S7, hairy, and apical portion of S6, hairy

Wednesday, 21 May 2014

Philoganga vetusta - the big, the bold, the beautiful

When I first noticed the Ochre Titan in Tam Dao I was shocked by its robustness. This is a very large damsel and very strongly built. I ran into it again in Xuan Son and apparently it is not all that rare in spring. On 17 and 18 May I saw them in Tam Dao from low down up to 350m asl in good numbers, meaning at least 15 or so. Here are a few shots.

The mature male, with extensive orange to the abdomen and ochre to the flanks.

The massive female, sometimes whitish, sometimes ochre

And another male, maybe immature? The wings look old and worn. Is this pruinosity and this in fact a very mature specimen?

Coeliccia ambigua

When exploring along the road to Tam Dao 2 in Tam Dao National Park on May 17, along a stream deep in the forest, I ran into many Coeliccia ambigua. A really lovely species. It was also the first time I saw the female. After all the Gomphids and Calicnemia entries, time for a little diversion. There is some discussion on the affiliation of this species. Some place it in Indocnemis (with I. orang), based on venation. There are however also aspects of wing venation that better fit Coeliccia.

Copula of Coeliccia ambigua

The lovely male of C. ambigua

And the female. Females are confusingly similar amongst Coeliccia species. Maybe the combination of blue markings on the abdomen, light green thorax stripes and yellow venter to thorax could be characteristic?

Asiagomphus acco - a great species

Asiagomphus xanthenatus acco was described as a subspecies of A. xanthenatus by Asahina, but the rather different appendages prompted its elevation to specific status (Do Manh Cuong, and see also Karube). I saw it once last year, in Ba Be, towards the end of July. I was very happy to renew my acquaintance with it, when on May 18 I did not see one, not two, but many at about 300m asl in Tay Thien (Tam Dao). Here a few shots.

The male of Asiagomphus acco, with extensive yellow S1-2 and black S3-8.

Dorsal view of appendages

And lateral, note the tooth halfway on the venter of the superior appendage

And in ventral view

Sinorogomphus sachiyoae

18 May I found myself checking the streams around Tay Thien. At the end of the day I saw a slender and large dragon cruising over a stream at about 300m asl. It was not difficult to catch and in hand it was obviously a Sinorogomphus species. Although very similar in outward appearance to other Sinorogomphus species, the typical appendages allowed for identification as S. sachiyoae, a species known from Tam Dao and recently also recorded from Xuan Son by Sebastien.

Like all Chlorogomphids, a very attractive species! Sinorogomphus sachiyoae, male

Note the notch in the tip of the superior appendages. These also have a large lateral tooth, but that is difficult to see in this picture.

In dorsal view the lateral tooth of the superior appendages is visible. Note the deep V in the epiproct.

More details of Calicnemia haksik* **

* This post was adjusted after true identity of C. uenoi was established.
** This post was adjusted after the identity of C. mortoni was rectified as C. haksik.

A few weeks back I found a blackish Calicnemia in Yen Bai with just a little red at the beginning of the abdomen, superficially like C. haksik. But I postulated it is in fact C. uenoi, based on the structure of the appendages and coloration, although Asahina (1997) described more segments reddish. Now I found a few C. mortoni of which I could take close-ups to prove at least that the Yen Bai species is not mortoni.

Calicnemia haksik, male and female
C. haksik appendages
C. uenoi appendages

C. haksik penile organ ventral
C. uenoi penile organ ventral

Tuesday, 20 May 2014

The Heliogomphus enigma

When exploring around Nam Bung earlier this month I saw quite a few Heliogomphids that I identified as Heliogomphus scorpio based on the shape of the (all black) appendages. In fact, Sebastien Delonglee also had identified this species as such (see also his blog). However, when checking streams low on the Tam Dao range last weekend I noticed that the appendages of the Heliogomphids there seemed different. Interestingly, Sebastien during his visit to Xuan Son noticed the same. I asked Dr. Karube and he told me he was aware of two different types of Heliogomphus, but that apart from the appendages the species were very much alike. Nevertheless, we all agree that these actually are two different species. The identity of the Yen Bai type, in fact that also occurs around Tam Dao, is unknown for the moment. The species I encountered at Tam Dao now (and Sebastien at Xuan Son) is the real Heliogomphus scorpio.

The Yen Bai Heliogomphus, very yellow and long appendages
The Tam Dao Heliogomphus scorpio, much paler and different appendages
The appendages in dorsal view of the unidentified species

Those of the Tam Dao Heliogomphus scorpio. Both superior and inferior appendages are differently shaped

The unidentified species, note the double tooth on the basal process

The same for Heliogomphus scorpio, a much longer process, but no double tooth

Not all that glitters is gold, sometimes it is Rhinocypha orea

Rhinocypha orea was described by Hamalainen & Karube based on specimens collected around Tam Dao in the 1990s. It was still seen by Do Manh Cuong in 2005, but development around Tam Dao village has been rampant and pollution of the surroundings profound. There was hope that this beautiful jewel would be elsewhere on the Tam Dao mountain range, but some feared it was lost. It was therefore wonderful that I saw one male on May 17 in the forest along the trail to Tam Dao 2. This is at approximately 1000m altitude, close to the altitude of the earlier records. I saw it perched on a bush in the forest under heavy tree cover, by a small stream. It came as another surprise when on May 18 I saw another male near the Tay Thien monastery, at only 300m asl or so, again in the forest perched on a bush. If it also occurs lower in the forest, there is hope it may still be around in some numbers. As far as we know, it is restricted to Tam Dao.

Rhinocypha orea, male. Very dark species with golden gloss on inside of hind wings and green gloss on tips of hind wings on the outside.

Rhinocypha orea, male

The beautiful golden top of the wings, difficult to see in the field

Monday, 19 May 2014

What goes there in the shade - Idionyx and Macromidia

May 17 and 18 at Tam Dao I was lucky enough to run into several of those interesting Cordulids that lurk mostly in shady places, dart out over shaded clearings in erratic flight and otherwise hang somewhere in the dark. Only under cloudy conditions or towards the end of the day do they really venture out in the open, but they are sometimes quite common. These are the Idionyx species, with their imposing appendages, and the Macromidia species. They look superficially quite similar, although the males of Macromidia miss the weird appendages of Idionyx. The females look even more similar. I saw a few Idionyx carinata females on the Tam Dao 2 trail, so at around 1000 m asl. But in the lowland stretches of the streams in the Tay Thien area I saw several handful. The problem of course that they are difficult to catch and I only managed females. Checking in the field they had no horns, so I thought they would all be Macromidia. One was decidedly larger but the four others were all the same small type with large yellow basal markings to the wings. Under the microscope there are interesting differences in the shape of the vulvar lamina. The one female had the lamina shaped into a deep V as is normal in many species. But the smaller specimens had the two halves firmly closed together. This did not look like the same genus after all. The larger species is Macromidia rapida, a common species in the Tam Dao area, although not easy to find. Although M. genialis shanensis could also be present, that species has some different markings on the thorax and face. It also, apparently, misses the small brown markings at the base of the wing. The smaller species in fact belong to a group of small Idionyx that miss horns on the vertex. This could be either I. yolande, I. victor or I. thailandica. I. yolande and I. victor have a slightly different thorax pattern (although that of the female published by Karube (2011) looks very similar). I. victor also has apparently less yellow at the base of the wing. The present species is therefore I. thailandica. In fact Sebastien Delonglee also reported having caught this species in the Tay Thien area (including males). I too will be keeping my eyes open for the male in the next few weeks. Coincidentally, what also separates these small Idionyx species from Macromidia are the yellow shins and the different ventral pattern.

Macromidia rapida, female, and Idionyx thailandica, female
Macromidia rapida, female. Note brown on dorsum of thorax, brownish-yellow face and dark brown bases to the wings.
Idionyx thailandica, female. Note yellow shins (not just this species), large ochre bases to the wings and lack of obvious lamina in lateral view (again, indicative of the genus, not the species). The straight yellow line over the spiracle is indicative of the species.

Idionyx type of vulvar lamina
Macromidia type of vulvar lamina
In lateral view, no obvious lamina visible for Idionyx

But obvious for Macromidia

Belly pattern of Macromidia rapida, female

Very different belly pattern of Idionyx thailandica/yolande group of females