Some interesting gomphids from Quang Nam

On 25-27 September I visited Quang Nam Province around P'rao on the HCM Highway. I ran into quite a few interesting gomphids and I would like to share here some of them. Price for most interesting on the 25th goes to a Leptogomphus species. Recently I had a conversation with Haruki Karube on Leptogomphus uenoi, for which he recently published the male. Before that the species was only known for females and one could argue that the male leads a secretive life. But we concluded that maybe it was just overlooked, as the appendages are rather similar to those of L. perforatus. Well, I caught a Leptogomphus and in hand concluded it was probably L. perforatus, but somehow the ring of the inferior appendages seemed closed and I decided to collect it. Lucky too, for at home it dawned on me this was L. uenoi! The outer edge of the inferiors is straight, but the inside edge curved.

Leptogomphus uenoi male, a typical Leptogomphus species

But look at the appendages! A neat ring and almost straight outer edges.

 On the 26th I bumped into a multitude of interesting species. I was very happy to see quite a few Nepogomphus walli. Males were congregating in a fern at a particular stretch of the stream. I had so far only seen this species in Cao Bang Province.

Nepogomphus walli in hand, with its typical yellowish wollen base of the superiors

One of the males perched, this one not on a fern

Also interesting was the Lamelligomphus sp. that I had seen in spring much further north, in Nghe An Province. It was quite common here.

Lamelligomphus sp., a smallish species with interestingly very dark S2. Some individuals had a small yellow spot posterior of the auricle. It is similar to L. hainanensis, but has no protrusion of the inferiors.

A real surprise was the Nychogomphus flavicaudus on a larger river, where 3 males were hovering in the middle of the day. There were no differences with the specimens from Cao Bang I recorded in spring. Same size and same pattern on the thorax (only an antehumeral spot).

Male Nychogomphus flavicaudus, at least, if flavicaudus is a valid species

The last cool species I want to introduce here is Burmagomphus divaricatus. I had only recorded a freshly emerged specimen in Cao Bang in spring, but here I saw several adult males.

Here is one of the males in hand. The pattern on the dorsal side of the thorax is a little variable.

Another, similar, male perched

And the appendages in dorsal view

A Lamelligomphus feast - two additional species

Lamelligomphus is a fascinating genus of pretty much similar looking gomphids with massive and impressive appendages. They have a habit of hovering over fast streams, often again active towards dusk. Absent from Do & Dang, I soon found out that they did in fact occur in northern Vietnam, as is evident from the various entries on the genus in this blog. Additional species occur in the south (for sure L. castor), but I focus on the north. After verifying L. camelus and L. formosanus, both easy to recognize, L. camelus due to distinctive appendages and typical humps on S8 and L. formosanus due to the extensively protruding inferior appendages, raised distal carina of S8 and typical penile organ and thumb-like extension of the anterior hamule, the first hurdle was the unidentified species that recently was described by Karube as L. vietnamensis. This species is very similar outwardly to L. hainanensis, another species often encountered. But L. vietnamensis is larger (similar in size to L. camelus and L. formosanus), without any protrusion of the inferiors, antehumeral stripes connected to collar and line over frons interrupted. Smaller L. hainanensis has similar anterior hamule and penile organ, but generally black labrum (sometimes with two small spots), uninterrupted stripe over frons and normally no connection between antehumerals and collar. Importantly, it has a limited, but obvious, protrusion of the inferior appendages.

So, four species, and all in their inconspicuous ways different. And that was that. Or so I thought. The first crack in this simple scheme occurred on June 13, when I was checking a stream in Nghe An Province. This was a small species, like L. hainanensis. But the pattern of the face and on S2 was different. Triggered by this inspection of the appendages showed the lack of any protrusion. In fact it looked like a miniature L. vietnamensis. Penile organ and hamuli were in accordance with both these species. However, it is neither and appears to be an as yet undescribed species.

On June 22 I had a nightmare of an afternoon in Lang Son, having gotten caught in a terrible thunderstorm on an unpaved road in the mountains that had been turned into something reminiscent of Verdun by trucks. There was no way back and I continued struggling in 4WD motion at a speed of 8km an hour average. Towards dusk I got closer to national road 4 and in flatter terrain and crossing a stream decided to give the last moments of the day a try. The obligatory Lamelligomphus was hovering over the water, but in hand showed many characteristics that I had not seen before. The extensive lateral patterning was one, the indistinct humeral line another. Combined with the lack of a thumb-like extension of the hamulus (verified under the microscope), the lack of raised distal carina and other characteristics L. formosanus could quickly be ruled out. That species, although not in the populations I have seen in Vietnam, does sometimes have more extensive patterning. But it was not that. The key in Chao proved helpful. I tentatively identified it as Lamelligomphus tutulus, an addition to the Vietnamese list, but one that has been verified by Wilson for both Guangxi and Guangdong in neighboring China.

Let's start with something easy: Lamelligomphus camelus, with clear protrusion and humps. It also has a distinct boomerang on S2.

As can be also seen in this specimen in hand. This year alone I have seen this common species in Lang Son, Phu Tho, Bac Giang, Yen Bai, Thanh Hoa, Nghe An and Ha Tinh Provinces.

This is the recently described L. vietnamensis. No protrusion, but fairly large species. No humps and no raised distal carina on S8, amongst others.

Another male in hand. This spring I have seen them in Thanh Hoa, Cao Bang and Lang Son Provinces. Not rare, but not as common as L. camelus.

No this is the exciting L. species novum from Nghe An. No protrusion and only a single egg-shaped spot on S2.

Facial pattern not dissimilar to L. hainanensis, but frons with separation and labrum with spots.

These are its appendages, no protrusion at all.

Compare this to these appendages, of a male L. hainanensis

These are preserved specimens, with L. species novum on top and bottom L. vietnamensis, showing the obvious difference in size.

And no it is time to turn to the star of this blog entry. Lamelligomphus tutulus. Note metepisternum with three separated spots, both a humeral spot and indistinct humeral line, extensive yellow pattern on S1-2.

Facial pattern with large markings on labrum, bases of mandibles and lateral on postclypeus.

Very interesting appendages, protruding well, but different in shape from for instance L. formosanus.

As can also be seen in this dorsal view

A few more goodies from Xuan Son

October 26, in Xuan Son, I had, besides the Calopterygids and Planaeschnids, several other interesting dragonflies. Rhinagrion hainanense is always a great find. Regular at Xuan Son from early spring until autumn, but a wonderful insect. I was also surprised to see a female Merogomphus pavici ovipositing. I had no idea this species flies this late in the year. And two males Lamelligomphus formosanus were another surprise. Of course some Lamelligomphus fly relatively late in the year, but I had not seen L. formosans this late. Boyeria karubei was common, but it is a fine species and a specialty of the park. I also took a few photos of Coeliccia. No less than 6 species were present: C. scutellum, C. pyriformis, C. cyanomelas, C. uenoi, C. sasamotoi and C. poungyi.

Old male Lamelligomphus formosanus, its venter covered in mites.

Pretty Rhinagrion hainanense, male

Female Boyeria karubei

Female Merogomphus pavici, resting after release

Merogomphus pavici, female face

Closer in-hand view. Note the massive hind legs and the spines on it.

Coeliccia poungyi, one of about 12 males

Male Coeliccia sasamotoi

Lamelligomphus sp. - a new species after all?*

*This entry slightly adjusted now that the Lamelligomphus sp. has been described by Karube (2015) as L. vietnamensis.

Last year in October I caught a Lamelligomphus (see the entry) that until now I have not been able to identify. Sebastien also had photos of similar specimens, but only recently did we see it again. In August Sebastien informed me he had seen several in northern Vietnam and this weekend when visiting northern Bac Kan Province I too caught up with it again. I had a single male hovering over a clear stream that I could catch. Superficially it is like L. hainanensis. It has similar penile head shape, similar anterior hamule shape, no humps on S8, small teeth on the interior of the superior appendages. Indeed, I had thought previously this was L. hainanensis, until I found it earlier this year. But what I call L. hainanensis has a continuous green-yellow stripe over the top of the frons, even if it is slightly incised. The Lamelligomphus sp. (now Lamelligomphus vietnamensis) has the stripe clean cut into two parts. Also, L. hainanensis has all black or only slightly marked labrum, whereas the present Lamelligomphus has two clear yellow spots on the labrum. The inferior appendages are more blunt and do not project at all beyond the superiors. In dorsal and ventral view there are also small differences. And where L. hainanensis is a smaller species, with abdomen 41-42 mm, in the present species it is 47-48 mm. It is clearly a common species, has undoubtedly been overlooked (like L. formosanus), but I cannot fit it onto any known Chinese species. It is close enough in structure to L. hainanensis, but there cannot be two species with the same name, obviously.

Lamelligomphus vietnamensis. Typical as the genus goes.

Compare this photo of an earlier L. hainanensis. Very similar in overall patterning, but longer overlap of inferiors, which also clearly protrude.

Dorsal view of Lamelligomphus vietnamensis.

This is the face of  Lamelligomphus vietnamensis. Note the broken line over the frons and the large oval spots on the labrum. The yellow over the anteclypeus is, I think, normally continuous.

I already published this photo of face of L. hainanensis with continuous stripe over frons and all black labrum. Sometimes there are small yellow spots  near the sides (actually also in this specimen). 

Dorsal view of appendages

Ventral view

And lateral view. The short inferiors that do not protrude at all typical

Penile organ by the looks of it similar to L. hainanensis

Ophiogomphus, Lamelligomphus and Melligomphus

Ophiogomphus longihamulus was described by Karube (2014) from Pia Oac Nature Reserve and I spent a great deal of time looking eagerly for it. Eventually, on July 8, I finally ran into an Ophiogomphus. But it was not to be. It was Ophiogomphus sinicus. In itself a great discovery, and especially interesting because it shares the same habitat and general area with O. longihamulus. That species was observed in May, so maybe O. sinicus appears later. The two species, by the way, can be separated on the basis of, indeed, the length of the hamulus.

Ophiogomphus sinicus, Cao Bang Province, July 8

In hand, the same male

And close-up of the appendages

 Two species of Lamelligomphus were also very common. I saw Lamelligomphus camelus in the provinces Phu Tho, Hoa Binh, Bac Kan, Ha Giang, Yen Bai, Lang Son and Cao Bang. Lamelligomphus hainanensis was much less common. I saw that species in Yen Bai on mountain streams and likewise in Pia Oac Nature Reserve in Cao Bang Province. It is smaller than either L. camelus or L. formosanus and has smooth dorsum to S7-10. Whereas L. camelus is active during the day and at dusk, L. hainanensis seems to be active only during the day.

An obelisking male Lamelligomphus camelus, a common species

Much less common, male Lamelligomphus hainanensis

Another male, right in the act of spraying some liquid from its abdomen. He did this several times. I have no idea what this behavior is.

Lamelligomphus hainanensis, male, in hand. Pattern on S1-2 close to L. formosanus, without the boomerang of L. camelus.

Female Lamelligomphus hainanensis hovering over a stream and preparing to drop egg-ball

A female in hand

Close-up of the female face, showing the double horn on the occipital ridge

 The last species of this posting is Melligomphus ardens. This species too is active at dusk. In fact, although I have saw it during the day at a river in Bac Kan Province, almost all observations this year (at Phu Tho, Cao Bang, and Bac Kan Provinces) were at dusk. At the places where I saw it at dusk, I did not see any during the day.

Melligomphus ardens, male, 26 June, the only male seen in bright day light