Pia Oac in October - continued

I had a fascinating day at Xuan Son this weekend, with a plethora of Planaeschnids. That is a mixed blessing, as writing up is going to be a headache. So first a few goodies from Pia Oac on October 18. Amongst the few damsels that I saw while looking for Aeshnids I took photos of a few.

First to show is this wonderful male Ceriagrion fallax, a common species at this altitude, but always beautiful and more so with the bit of moisture clinging to it.

Then I was lucky enough to bump into a copula of Noguchiphaea yoshikoae. No idea what the function of the horns is on their prothorax. In close-up they run parallel to the male paraprocts holding her, but apparently without interaction.

And finally this well mature female of Ischnura carpentieri.

Shall we "Planaeschna"?

* This post was updated on November 15, 2025. Planaeschna has been synonymized with Aeschnophlebia. Also, Kompier et al. (2021) treated the Vietnamese species of the genus in detail. Adjustments have been added below between square brackets []. All references to P. tomokunii below are in fact other species (P. crux and P. samurai) and P. gressitti is in fact P. tamdaoensis, which in turn is likely a junior synonym of P. suichangensis, see Kompier et al. (2021). 

A few weeks back I caught both several Planaeschna gressitti [= Aeschnophlebia gressitti] in Pia Oac and a P. tomokunii lookalike female [a species described in Kompier et al. as Planaescha [= Aeschnophlebia] crux]. I started thinking about some of their identifying features. For one, P. tamdaoensis, as described by Asahina (1996) and P. gressitti (Karube, 2002) are very similar in patterning, both on the body and on the face. Differences appear when looking in detail at the appendages and penis. I was quite confident that the specimens collected in Pia Oac were P. gressitti, just as those, at similar altitude from Mau Son. The fact is though that these locations are far removed and that Tam Dao is sort of in between. P. tamdaoensis therefore occurs in the middle of the P. gressitti range and at similar altitude (around 1000m asl). Both the specimens from Mau Son and from Pia Oac had the nice balloon-shaped distal segment of the penis, quite unlike that drawn by Karube for P. tamdaoensis (although this is not depicted in the original drawings of Asahina). Apparently it was drawn later. I did not think more about this at the time, as it seemed to be straightforward. But last weekend (Saturday October 18) I went back to Pia Oac and was lucky enough to catch a male P. tomokunii lookalike [it later became clear that this is not the male specimen of the same species as the female A. crux. The male is in fact A. samurai], just some 25 meters from where I had caught the female two weeks earlier. It is larger, closer to P. tomokunii and fits all characteristics. It had however a balloon-shaped penis, quite different from that drawn for this species by Sasamoto et al (2013). I was confused and pondering. Might it be that the changes induced post-mortem and after preservation alter the configuration of the penis? In most cases this is not the case, but maybe it was different for Planaeschna species with their bloated and soft organs? In fact, as below pictures show, this is very much true. Photos of fresh specimens are balloon-shaped, but after their acetone bath they are greatly changes, both in color and in shape. This makes this characteristic, in my view, unreliable, given that most drawings are done in the lab a while after preservation and not on the fresh specimens. The differences in the appendages of P. tamdaoensis and P. gressitti may well be real, but these too twist sometimes upon drying and the exact shape can only be ascertained three dimensionally when differences are slight, as is the case in many Planaeschna. This is not to say that P. gressitti and P. tamdaoensis are not different species, but given the paucity of available material, I would not be surprised if they eventually would turn out to be conspecific.
If we disregard the penile organ shape for the P. tomokunii lookalike and the slight differences in the appendages, but consider the great similarity on patterning and structure, plus the fact that the male is only 2 mm smaller than the specimen described by Sasamoto et al, it would seem likely that this and the female of two week earlier, are in fact that species. The female then is just a small specimen.

First, let's have a look at fresh distal segments of the penile organ in ventral view, and compare to their post treatment shape:

The fresh distal segment of the penis of P. tomokunii in ventral view, very whitish and with globular and divided apex.

The same segment after preservation. Much reduced, the earlobes directed in the opposite direction, the color yellowing brown and the apex no longer divided, but forming one continuous shape.

The same segment in a fresh P. gressitti male, also very globular and with a split apex.

A P. gressitti male after preservation. In this case the globular effect is completely gone, the sides now straight and angular, although the split in this case is still present. Again the earlobes completely distorted. This is almost (apart from the direction of the lobes) the shape of the segment as drawn by Karube for P. tamdaoensis, indicating that this feature is unreliable.

Male Planaeschna gressitti (left) and P. tomokunii (right), both collected on October 18. P. gressitti with two yellow spots on dorsum of S10, not seen in the others I collected. [For clarity, the left male is Aeschnophlebia tamdaoensis (which is likely a junior synonym of A. suichangensis) and the right male is A. samurai.]

Male P. tomokunii. Note the reduced dorsal patterning on the abdomen with only central dorsal spots from S5 onwards.

Dorsal pattern on the thorax

Facial pattern, with largely pale-yellow labrum, with darker lower border, postclypeus with two orange pits and brownish center to the frons. Very similar to the female.

Dorsal view of appendages of P. tomokunii, more slender than P. gressitti

Lateral view of the same with relatively broad superiors

And the same ventrally

Coeliccia galbina - a cool addition to the Vietnamese list

Sunday October 19 turned out to be a nice day, so I drove to Huu Lien. I had not been there for a while and wanted to collect a few of the Paracercion (yes, not Pseudagrion, we know that know thanks to Xin Yu) species novum for descriptive purposes. I did not expect new things so much, because we had visited Huu Lien many times last autumn. Indeed, most was familiar. But on the way back through the forest I noticed a large damselfly. Female Indocnemis orang, I thought, based on size and thorax pattern, but then I noticed vague orange appendages. Was this a male? Then what is this!? I did not dare take pictures in situ, but decided to catch it and take pictures in hand. Indeed, this was clearly an unknown Coeliccia species! At home I checked what literature I have and finally came upon Wilson & Reels' paper on damselflies in Guangxi (2003). They described a new Coeliccia, C. galbina. In fact, in the detail of the description it differs in the color of the stripes on the thorax, more yellow/green in the blue, and the same for the lateral markings on S1, but other characteristics are a close fit, and indeed penile organ and appendages fit too. This species is remarkable for the vague orange markings on S9-10, that have a hint of blue, and the pale orange appendages. I do not know how many records there are from Guangxi, presumably few if any besides the types. Two were collected in May, one teneral, from limestone karst hills in Longrui, in the Southwest of Guangxi. It is probably no coincidence that Huu Lien is also limestone karst hills. Longrui is about as far from Huu Lien as Hanoi. In other words, just around the corner.
The slightly more blue, not yellow/green in the thoracic markings I postulate as caused by the maturity of the specimen compared to the May specimens of the description. Such change is very common on blue Coeliccia species.

A fantastic find: Coeliccia galbina, male, new for Vietnam

The same male in dorsal view

The appendages and S9-10 in dorsal view. Note the strange orange-blue (purple) markings and pale orange appendages

Appendages in lateral view, the superiors with a ventral process with a black tooth

The penile organ, distinctive

Looking for Aeshnids

* This post was updated in November 15, 2025. The genus Planaeschna has been synonymized with Aeschnophlebia. Kompier et al. (2021) dealt with the Vietnamese members of this genus. Below adjustments are made between square brackets [], detailing the proper names.

After last weekend in Pia Oac and the not-quite Planaeschna tomokunii [in fact this refers to a specimen of A. crux], I decided to see if I could find a male. I woke up to a bright and sunny Pia Oac on Saturday morning and soon caught another male Planaeschna tamdaoensis [=Aeschnophlebia tamdaoensis], but from that moment my luck changed. Although I saw quite a few Aeshnids on this in the end rather cloudy day, I failed miserably with the net and did not catch any. Especially bothersome, because some certainly were not P. tamdaoensis, not likely P. cf. tomokunii for that matter. I did get a few better shots of Vestalaria smaragdina this time, and my first andromorph female Ischnura carpentieri, when I spotted what looked like a male ovipositing. Of course in this genus this is not uncommon, but whether or not it is also common in this species I do not know. Otherwise the birding was relatively good, with a large flock of Grey-headed Parrotbill, a new species for me, and pretty dandy Golden Parrotbills in another good flock.

Sunday I went to Tam Dao, to find the real Planaeschna tomokunii, but I did not see anything really, although I was happy to take photos of female Megalestes haui and it was good to see Coeliccia scutellum. This is a common species, but I had been spending relatively little time in places where they occur this summer, so it was good to meet again. Otherwise this day was enlivened with a flock of 24 Crested Serpent Eagles lifting off from a small hill in the plain to start their day's migration.

Female Ischnura carpentieri eating a bug after ovipositing

The male for comparison, note the brighter pterostigmata (amongst others)

Megalestes haui male from Pia Oac

Megalestes haui female from Tam Dao, above the village

Yes, I know, this is a dragonfly page and it is a shitty photo, but hey, recognizable, Grey-headed Parrotbill

Male Vestalaria smaragdina. Note the long inferior appendages and unmarked wings.

Male Noguchiphaea yoshikoae, also from Pia Oac, showing for instance the apical dark spot on the front wing

An amber-winged female of Vestalaria smaragdina. Note the lack of horns on the prothorax. 

Male Coeliccia scutellum, having just dropped the bug it was eating (now on the leaf between the legs)

Leftovers from Pia Oac

A bit of a misnomer, leftovers, for these wonderful species that I also took pictures of on October 4.

This is Ischnura carpentieri in copula, the male easy to recognize (as member of rufostigma group at least), the female notoriously difficult. A common species in the mountains.

Sympetrum hypomelas does not only occur in Sapa, but also in the lower mountains of northern Vietnam, like here at Pia Oac at approximately 1000m.

This is a male Macromia moorei, still surprisingly common this time of the year at Pia Oac. Note the almost complete band on S2

The same male in dorsal view and under flash

And in hand, showing the obvious lobe that distinguishes it from M. pinrantani vietnamica

Planaeschna cf.(not quite) tomokunii - a great find at Pia Oac*

** This post was updated November 15, 2025. The genus Planaeschna has been synonymized with Aeschnophlebia. Also, Kompier et al. (2021) sorted out many earlier misconceptions regarding Vietnamese Planaeschna species. Below adjustments are made between square brackets [] to clarify.

*Subsequently (October 18) a male was caught and it appears to be P. tomokunii after all. [This note was wrong, the female belongs to a species described as Planaeschna crux, now Aeschnophlebia crux, and the male as P. samurai (now A. samurai)]

After the splendid male Planaeschna gressitti [= Aeschnophlebia tamdaoensis, possible junior synonym of A. suichangensis] at the pass of Pia Oac, we saw another Planaeschnid at the gold digger stream, where it was hunting above the stream in a dark corner under a rock and tree near a rapid. Netted, it turned out to be a female. A slight disappointment, but I carried it home anyway. It was very small with a total length of only 63mm, small for the genus. But it also had some interesting characteristics. It had for instance quite a bland face, without clear bright and dark patterning. It also had very reduced abdominal markings on S4-7, with only a pair of medio-dorsal markings, but nothing anterior or posterior. These markings were also unconnected to the ventral spots. S8 had only a small yellow ventral anterior spot and S9-10 were all dark. On the other hand, S2 was completely yellow in the ventral half, and S1 largely so (but dark on the dorsum). The ventral projection of S10 is spine rich, in the words of Sasamoto et al. (2013).

This species is very close to Planaeschna tomokunii (Asahina 1996 and Sasamoto et al 2013) in general appearance, for instance the facial pattern, the pattern of the abdomen and thorax, and the spine rich projection. There are however several differences as follows: 1) S1 is not all yellowish, but has dark dorsum, 2) The medio-dorsal markings on S2-4 are not connected to the ventral spots, the nodal index is rather different (which may be due to the smaller size) but is 15-22/22-16:19-16/16-18 whereas in Sasamoto et al. it is given as 21-24/27-21:24-19/19-21, 4) the anal loop is 7-celled versus 11-celled in Sasamoto et al. for P. tomokunii and 5) the FW triangle is 3-celled, against HW 4-celled, which is strange in the genus where normally the FW has more cells than HW. In Sasamoto et al. it is FW 5-celled against HW 4-celled. The overall size of only 63mm against 72mm for P. tomokunii could be an aberration, something that also explains the differences in number of cells, but the additional differences in color pattern and the fact that the FW triangle number of cells is smaller than that of the HW makes me want to postulate this is in fact a different species, albeit similar. All other Vietnamese Planeaschnids can be excluded and I have not been able to find a Chinese species of similar appearance.

The female Planaeschnid cf. (not quite) tomokunii. Note the reduced abdominal markings, with even on S2-3 the medio-dorsal spots unconnected to the ventral markings

In dorsal view, showing the distinct Planaeschnid venation

The rather plain facial pattern, very good for P. tomokunii

Sieboldius nigricolor - the female*

*This posting was adjusted on April 1, 2016, after the identity of the species was finally established.

October 4, Pia Oac. We are standing in the gold digger stream and checking the Macromia moorei flitting up and down in surprisingly good numbers. Suddenly a large dragonfly comes near and I am able to catch it. It is a very robust insect, immediately recognizable as a Sieboldius by its small head and very long legs. It is excreting eggs, so I tip its abdomen in the water until all the eggs have been dropped. After that I put it in an envelop. Quite surprising really. Since the males caught early July I had not seen it anymore, but clearly it is still flying. Shortly after, a male shows up and perches on a rock in the stream. While I carefully make my way to it, a Grey Wagtail flies in and flushes it, but luckily it soon returns. Again I am lucky enough to catch it. It is indeed the same species as earlier in the year: Sieboldius nigricolor.

The female of Sieboldius nigricolor

The male of Sieboldius nigricolor

Male and female united again under the scanner in dorsal view