Sunday, 22 November 2015

The male of Gynacantha basiguttata and a male G. japonica thrown in

November 21 I went to Huu Lien to look for the enigma Planaeschna cf. guentherpetersi again, but did not see it. I did catch an Aeshnid that passed overhead in the forest and was very happy to find it was a splendid male Gynacantha basiguttata. I had caught the female a few weeks back too. Apparently it is not that rare inside the forest. The other cool thing I saw was a communal roost of Cratilla lineata. I had seen that in Potamarcha congener, but this was new knowledge to me. At least 15 bundled together on a hanging twig.

On November 22 I went to Xuan Son and looked for the small pale-faced Planaeschna there. I did see one female, but failed to catch it. It was mostly an uneventful day, but I saw a few Gynacantha japonica and was able to take some pictures. Another unexpected species was Trithemis pallidinervis at the river crossing, which I had not seen this far north. And a fine male Ceriagrion bellona was another nice one. Not at all that common, although regular at Xuan Son.

Very fine male Gynacantha basiguttata, note the dark wingbases.

Scan of the same male. Note the long and slender epiproct and the wingbases.

Pretty male Ceriagrion bellona

Gynacantha japonica, note the pale epiproct.

And a surprise female Trithemis pallidinervis

Wednesday, 18 November 2015

Coeliccia sp. - an intriguing species from central Vietnam*

*This posting was originally on C. montana, but it is now clear, after studying of the type material, that this species has been misidentified by Asahina. It is in fact an undescribed species and will shortly be published.

The last weekend of September I was hunting for dragons along the streams of Quang Nam Province near Bhalee village. I found a handful of pretty, smallish Coeliccia that I did not see before. Superficially they are similar to the even smaller undescribed species occurring in Cuc Phuong National Park and Huu Lien Nature Reserve, especially the males. The males have a black dorsum to the thorax, with two yellow spots at the proximal end, although larger and more elongated than in the C. sp. nov. They also have a black line along the metapleural suture absent in that species. Another difference is the abdominal pattern, which has much clearer rings. And very interestingly, they have a pruinose prothorax. I know only of C. ambigua as having pruinosity, but that also covers most of the thorax. It looks rather similar to the Indian C. schmidti Asahina, 1984, but that species misses the pruinosity on the prothorax, amongst other minor differences, and has a very different female, with bright yellow prothorax and broad antehumeral stripes. The female of the present species has a very distinctive prothorax with horns on the posterior lobe, reminiscent of the Indian C. vacca Laidlawi, 1932. It is different from the C. sp. nov. also by its thorax pattern, which has a thin antehumeral stripe, broader at the proximal end. Sadly, I let it get away (good for her) so do not have a close-up of the exact configuration.

I identified the species after consultation with Philip Steinhoff and Do Manh Cuong as C. montana Fraser, 1933. Although in their redescription of 2013 they did not mention the pruinosity and although the specimen they illustrated had "paddle sticks", meaning that the yellow spots on the thorax are elongated at the distal end into a thin antehumeral line, penile organ and appendages are a close match. Philip mentioned that specimens he considered C. montana from Da Nang also missed the paddles and that a female from the same location as those males also had the distinctive horns. What is more, on photos of his preserved specimen from the redescription pruinosity is visible on the prothorax (considered dust at the time). It therefore seems reasonable to assume the northern specimens of C. montana miss the paddle sticks of their southerly brothers. Remains the original description by Fraser, which mentions pale blue rather than yellow for both the lateral sides of the thorax as for the antehumeral stripe, although facial markings are yellow. It is possible that the change in colour is due to postmortem change, or due to preservation. Fraser also describes the abdominal tip (S9-10) as blue dorsally and laterally, but black ventrally, for adult, the blue replaced by yellow in immatures. The description also does not mention the pruinosity on the prothorax. Fraser's specimen is from Laos, whereas the redescription of the species by Asahina (1969) from southern Vietnam describes the pattern on the thorax as yellow and the abdominal tip as yellow all around. Nevertheless Asahina concludes his specimen agrees "rather well" with the type specimen in the British Museum of Natural History. Given how close many species resemble others, "rather well" seems not so convincing, especially given the differences in color and patterning. If Asahina's species is not C. montana, then the species redescribed by Steinhoff & Do also is not C. montana. In identifying my specimens as C. montana I therefore mean C. montana sensu Steinhoff & Do. Philip is trying to inspect the type in the BMNH, which may help to set the record straight.

*It is now sufficiently clear that "southern" and "northern" montana in fact are two different species and neither is C. montana. Both are currently being described.

Male Coeliccia montana. Note the darkish abdomen, pruinose prothorax, yellow dorsal spots on the thorax.

The female in hand. If you look carefully, you can see the distinctive horns on the prothorax posterior lobe

Tuesday, 17 November 2015

Several new species of Protosticta for Vietnam*

*This posting was adjusted on April 7, 2016, when the name of this species was first published (Phan & Kompier, 2016) as Protosticta socculus. This species can be identified by the shape of the appendages (under the microscope, I am afraid).

At the end of September I observed several boldly patterned Protosticta specimens in Quang Nam Province, close to Da Nang in central Vietnam. I cannot publish them here yet, for their identity was a puzzle. In the meantime I have been working with Toan, who did the ground work for it, on an article on Protosticta species and this species is one of several we hope to publish soon. It is close in appearance to several other species with bold patterning of the thorax, like P. khaosoidaoensis, P. linnaei, and P. caroli. An intricate puzzle for sure. Once you get into the detail, this is a fantastic genus of many hard to identify species.

Protosticta sp. nov. from Bhalee, Quang Nam Province. Note the largely whitish prothorax, the boldly patterned synthorax and the pattern on the abdominal segments of whitish basal rings and brownish subapical rings. The true identification character is the shape of the inferior appendages.

Sunday, 15 November 2015

Sa Pa in autumn

This weekend I went to Sa Pa, because the weather forecast said the weather was going to be beautiful and because in Hanoi it was going to be mediocre. Well, Sunday it rained in Sa Pa and Hanoi was sunny. But Saturday was bright indeed. Even so, there were only 4 species still around. Anax nigrofasciatus and Ceriagrion fallax were two of these. Really common still was Sympetrum hypomelas. And Palpopleura sexmaculata was also still about. One mature male, but also a freshly emerged female, which was a bit of a surprise.

Birds were actually much more interesting. I ran into a Wood Snipe at a swampy woodland at 2000m along a small stream, which was a lifer for me and a really rare and difficult bird. That surely made up for the weather and the lack of dragons. The "tricolor" subspecies of Long-tailed Shrike was another surprise.

The male of Sympetrum hypomelas is a stunning creature.
Yet another one

When in the morning of Sunday the sun was still out, I climbed a mountain side without my camera and bumped into this female. So I took a photo with my telephone. Not too bad. I did not know the females turned this red late in the season, but they do. The red is restricted to the dorsal area between the lateral stripes on the abdomen.

Male Palpopleura sexmaculata. This species is awkward to take pictures of in close-up, because they keep their bodies at an angle and also drop their wings forward. This is not too bad.