Thursday, 12 May 2016

Another Sinorogomphus, but not very different

While visiting the mountains along the Laotian border close to Da Nang in the first week of May I caught a Sinorogomphus that looked very similar to S. sachiyoae. But the lateral pattern on S2 was somewhat different and upon close inspection the shape of the tips of the superior appendages was also different, if not a lot. I thought it had to be S. sachiyoae, but after consultation of the literature it turned out to be a species described already in 1969 by Asahina: Sinorogomphus vietnamensis. A nice and interesting addition to my list. In fact I observed the species in Quang Tri, Quang Nam and Thua Thien - Hue Provinces.

Male Sinorogomphus vietnamensis. Note the pattern on S2 and the fact that the superior appendages seem to touch the inferiors.
The female is even more like S. sachiyoae.

In dorsal view the appendages are quite similar

But in lateral view the tip of the superior appendage is longer and bends downward towards the epiproct.

Wednesday, 11 May 2016

A new species of Asiagomphus

April 17 I was checking streams near Tuyen Lam Lake at Da Lat. It started as a sunny day and around 9.30 I spotted the first gomphid, perching in the middle of the stream on a stone. It was immediately obvious from the extensive yellow on the terminal segments that this was something I had not seen before. It took some effort, but eventually I was lucky enough to be able to net it. In hand my suspicions that it was an Asiagomphus species were confirmed. A very interesting species, with extremely extensive yellow markings and widely expanded S7-9. Patterning was otherwise in line with Asiagomphus and the appendages were also typical of the genus. But it is not any of the other 4 species (at least) I have seen in Vietnam and it is not any of the known species from South-East Asia either. A wonderful species and new to science! It was rather common at the stream, with at least 10 different males observed and a few females seen ovipositing.

Asiagomphus species novum. Note the extensive yellow markings on S7-9. A beautiful and striking species.
A male in dorsal view, showing the massive club
And in lateral view
The appendages and terminal segments in dorsal view

Tuesday, 10 May 2016

The world of Protosticta

Once you start looking at Protosticta species, you will find there is a whole world out there! Only recently I published a paper with Toan giving details on the currently known 9 species from this genus for Vietnam. Two of these are large and different: Protostica grandis and P. ngoai. One has very typical appendages: P. spinosa. The remaining 6 are very similar. I had not yet seen several of these, but on May 5 in Quang Tri province I found an area where I kept bumping into one of these: P. caroli (first described by Jan van Tol in 2008). It can be identified by the only partially pale S9, the stubby inferiors (compared to for instance P. socculus) and the prothorax of which always the posterior lobe is extensively dark, which extends onto the central lobe. But really one needs a microscope to settle its identity for sure.

In the same area, but on a drier slope, I ran into what seemed a "very" different species. A little smaller, it was crispier, in that the white rings on the abdomen were really white, the prothorax had only on oval black spot in the posterior lobe, it has all white S9 and under the microscope there are also important differences in the appendages (like a missing lobe). Careful checking at home showed it was none other than P. socculus.

Relatively boring P. caroli. It shares with P. socculus the broad black line over the metapleural suture. S9 is only two-thirds pale, but not truly white, and the abdominal rings are likewise not very crisp.

Another specimen, similarly with limited white on S9.
A male in hand. This specimen has minimal dark markings on the prothorax, but still all dark posterior lobe, dark extending onto central lobe in two triangles, remainder off-white. The colour of the thorax is a dull dark green. 
P. socculus. Note the very white abdominal rings, the crisp white prothorax with contrasting posterior lobe
A close-up of the prothorax. Note also that the colour of the thorax is a different green.

Sunday, 8 May 2016

Macromidia kelloggi - a relatively solid Macromidia

In 2015 Karube published a record of Macromidia kelloggi from Bach Ma National Park close to Da Nang. This was far from known localities in China, but Karube postulated that the species in fact occurred widely in northern Vietnam. Because it has yellow antehumeral spots it is quite easy to separate from the common Macromidia rapida, but although I checked many, I never saw this species mixed in.

But today I was staking out Chlorogomphids (in vain) at Tam Dao when around quarter to four in the afternoon, so bright day, although it was cloudy with only intermittent sunshine, when a sturdy Macromidia tried to zip past me. But alas, it ended up in my net. Not only was it immediately obvious that this was not M. rapida because of its sturdiness and different appendages, it also had yellow antehumeral spots! Macromidia kelloggi, I presume? Indeed, indeed! A largish species, total length 60mm and hind wing 39mm.

Macromidia kelloggi. Note the yellow antehumeral spot (although small for the species)

Black base to ivory superiors and brown edged and tipped epiproct

Rather unlike the appendages of M. rapida (see under that species)