A Christmas safari - Da Lat - Con Dao - Phu Quoc*

*Adjusted on January 4, 2020. Euphaea pahyapi mentioned in this entry in fact concerns a different species now described as E. cyanopogon Hämäläinen, Kosterin & Kompier,  2019.

For a Christmas break Kameliya and I travelled to Da Lat, Con Dao and Phu Quoc. The first was good for 12 dragonfly species, the second for about 25 and the latter for 63. Needless to say, we were looking for a lot more than dragonflies, so this was not disappointing. Phu Quoc was out of season for some of the specialties, but with 63 species in 4 days of searching we still topped the 2007-2008 survey by Bui Huu Manh and its successor from 2011 by Do Manh Cuong et al. Floris Brekelmans in March 2015 found several additional species (notably Podolestes coomansi and Coeliccia kazukoae), so it was not surprising that there were still a few species that remained to be discovered.

On the list as given by Do et al. (2011) there are several species that were already present on the list of Bui, but judging from the photos in his photographic guide some of these are misidentifications. (Copera marginipes is clearly C. vittata, Cratilla lineata is Potamarcha congener, supposed Cratilla metallica looks to be Lathrecista asiatica, Ceriagrion auranticum looks to be C. calamineum, and Euphaea ochracea is the newly described E. cyanopogon.) Do et al. moreover suppose that the weird thoracic markings of Coeliccia yamasakii in Bui indicate a species novum, but I consider these immature examples of typical C. yamasakii. The unidentified Prodasineura is P. verticalis from southern Thailand. This is not to diminish the value of their pioneering work. They did much to map the beauty of the Odonate fauna of Phu Quoc, which is under severe threat from the break-neck speed of the development of the island. Waterways are getting polluted and depleted, wetlands drained and build-up. Clearly environmental considerations are not keeping up with the urge to make a quick buck.

I will over the next days publish photos of some of the species found. Here I limit myself to my list of Phu Quoc and photos of wonderful Rhinagrion viridatum, a highlight of the trip. This species was recorded as Rhinagrion mima, but Kalkman & Villanueva (2011) already pointed out that the inclusion of R. viridatum in R. mima should be revised and R. viridatum given full species status.

The first of 7 males of beautiful Rhinagrion viridatum

Another male of the same smashing species

The List:

Vestalis gracilis
Libellago hyalina
Heliocypha biforata
Euphaea pahyapi****
Ischnura senegalensis
Aciagrion borneese
Agriocnemis minima*
A. nana*
A. pygmaea
Archibasis viola
Ceriagrion cerinorubellum
C. olivaceum*
Mortonagrion falcatum***
Pseudagrion australasiae*
P. microcephalum
P. rubriceps
P. pruinosum
P. williamsoni
Coeliccia kazukoae**
Pseudocopera ciliata*
Copera vittata**
Prodasineura verticalis**
Anax guttatus
Gynacantha basiguttata*
G. bayadera*
G. subinterrupta*
Ictinigomphus decoratus meleanops
Paragomphus capricornis*
Epophthalmia frontalis*
Acisoma panorpoides
Crocothemis servilia
Orthetrum sabina
O. pruinosum*
O. chrysis
Pantala flavescens
Trithemis festiva
T. aurora
T. pallidinervis
Brachydiplax chalybea*
Brachythemis contaminata
Diplacodes nebulosa
D. trivialis
Hydrobasileus croceus
Indothemis limbata***
Lathrecista asiatica
Nannophya pygmaea
Neurothemis fluctuans
N. tullia
N. fulvia
N. intermedia*
Potamarcha congener
Pseudothemis jorina*
Rhodothemis rufa*
Rhyothemis phyllis
R. variegata
R. triangularis
Tetrathemis irregularis
Tholymis tillarga
Tramea transmarina euryale*
Urothemis signata
Zygonyx iris
Zyxomma petiolatum*
Rhinagrion viridatum

*   Refers to species first recorded on the island, although some are very common
** Coeliccia kazukoae had already been found by Floris Brekelmans, but is not rare. Prodasineura verticalis had been recorded as Prodasineura sp. Copera vittata had been misidentified previously (as C. marginipes), but is a very common species.
*** Refers to species recorded for the first time for Vietnam (as far as I know)
**** Refers to a species recorded for the first time for Vietnam, but misidentified in previous surveys.

Tetrathemis platyptera and Rhinagrion hainanense

On June 8 I was oding in Xuan Son. On the verge of the reserve I first visited the large stream and in some ponds bordering it I found a small dragonfly I had been looking for for quite some time. Last year in Ba Be I saw it from the corner of my eye, but although Sebastien saw them several times at Xuan Son (see his blog), I missed out. But there it was. And although I could only get some shots from a distance, I was happy.

Later, inside the reserve, I twice bumped into beautiful Rhinagrion hainanense. First a fresh female, just emerged from the stream along the dam and later a male along one of the minor streams flanking the large stream with the bridges. I featured it before in the blog, but this is a species you can never see enough of.

Cute, small, Tetrathemis platyptera, male. Yes, I know, calling a dragonfly cute is degrading to the insect, but hey, it is pretty.

Freshly emerged Rhinagrion hainanense, female

And yet another handsome fella. Rhinagrion hainanense, male

Philosina buchi

On June 7 on the way to Mau Son I could not help to check some streams in the general area where one upon a time Echo maxima had been collected. The stream along QL 1A is pretty polluted, but just north of QL279 there is a feeder stream that runs into it that is really not bad at all, even if it runs from a village somewhat further upstream. Maybe there are even better stretches past that village. We checked the stream and apart from a nice Nihonogomphus thomassoni / lieftincki (I now lean towards thomassoni, but if it is one and the same species, who cares) saw at least 15 Philosina buchi, sometimes 3-4 together. I also noticed interesting interaction between males. One male flew towards another and perched close to it, after which both at regular intervals raised their wings somewhat up in one short jerky motion. This lasted for a few minutes, until the original intruder flew off again. The remaining male thereafter sat still.

Philosina buchi, nice male

Two males in close proximity, the lower one had flown in just before and both were at regular intervals raising their wings somewhat in an apparent intimidation display.

Philosina buchi - Another addition to the Vietnamese list

May 1, Labour Day, I was working the streams of Huu Lien looking for Asiagomphus (amongst other things), when my attention was drawn by a large whitish insect with red on the abdomen. It turned out to be a fantastic spreadwing damselfly. I had seen it on photos, but did not immediately know what it was. Checking at home made quickly clear that it was Philosina buchi, a species widespread in Southern China, also in Guangxi and Guangdong, and as in so many other cases, it is not withheld by political borders. Its occurrence in Northern Vietnam is thus not unexpected. Here a photo of this fantastic damsel.

Male Philosina buchi, a stunning damselfly.

A few more Rhinagrion hainanense

October 26 we paid another visit to Xuan Son NP, with amongst others the objective to see more Rhinagrion hainanense and try to take pictures of it displaying. After all, that is one of the more fascinating sights in nature I have observed in a long time. But it proved to difficult, with only one male and one female about and the male nimbly buzzing around. So, I could only take picture of it tail-lifting in display when perched. Also, the female, ovipositing in wet mud. From the large and robust ovipositor one might think that it serves to penetrate wood, but no. With thanks to Sebastien for pointing it out by the water's edge.

Rhinagrion hainanense, male, exquisite!

Raising its abdomen in display

Female Rhinagrion hainanense, pretty!

Rhinagrion hainanense

This weekend I visited Xuan Son National Park again, because I had the feeling there was more to be found there still. And indeed, there was! Saturday was very misty and drizzly still; the aftermath of the Typhoon that passed in the days before. Sunday was however mostly sunny, and wonderfully dry and cool, about 23 degrees. Apart from some great birds I saw some very interesting species of dragonfly, enough to keep me busy on the blog in the coming days. In total I saw 8 new species, two Coeliccia, two Ceriagrion, a Planaeschna, a Rhinocypha, a Vestalaria, and last but definitely not least, Rhinagrion hainanense, which I will introduce here.

This fantastic dragonfly like damsel I bumped in to when I was checking a roadside pond of extremely clear water, filled by a clear stream that welled up in the forest nearby. The pond was man-made, dammed up to provide a place for washing at a shack just downstream. The pond produced the two new Ceriagrions too, but my eye was caught by something waving a little red flag at me. It turned out to be a male Rhinagrion displaying to a female perched on a branch. The male was hovering nearby, abdomen bend down and forward with the last few segments somehow spread out and bright red. The quivering motion made it seem like a bright red little flag indeed! Absolutely brilliant, I have seen nothing like it. When not chasing the females and displaying, it was sitting horizontally on a branch with wings spread out horizontally. Very unlike any damsel I have ever seen, hugging the branch like a little gomphid.

Rhinagrion hainanense

What an absolutely fantastic damsel!

Close-up shot in hand, the red ventral side of the last segments just visible

Rhinagrion hainanense, female