VietOdonata: Some goodies in and around Xuân Son

Fast-flowing stream with boulders, running through largely untouched forest, Xuân Son

My first 2 days trip of the season: Xuân Son National Park (140 km north-west from Hanoi). As the weather was cloudy, thus not optimal for forest dragonflies, I chose to focuse mainly on the open aspect streams and rivers around the park and found there 4 new species for my personal list: Orientogomphus naninus, Dysphaea basitincta, Pseudagrion spencei and Macromia clio. Other notable species were Macromia cuprincincta and the recently described
Lamelligomphus vietnamensis.

Within the park itself, Phaenandrogomphus tonkinicus was the only new species for my personal list.

Here are my best photos from this trip:

Lamelligomphus vietnamensis, male

Recently described from Tam Dao and Xuân Son NP (Karube, 2015)

Lamelligomphus vietnamensis, male
Was patrolling slowly a short section of open river, hovering a lot

Lamelligomphus vietnamensis, male in hand for better view

Lamelligomphus vietnamensis, male caudal appendages, lateral, apical and ventral views

Note the denticles in the inner corner of the curled part of the superiors, the tip of inferior appendage closely apposed to the superiors (no protrusion) - compare for example with the appendages of L. camelus in the photo below

Lamelligomphus vietnamensis has been recorded from Tay Thiên-foothills of Tam Dao (Vinh Phuc Prov.) and Xuan Son NP (Phu Tho Prov.) – type locality. Tom also recorded it from Bac Kan, Thanh Hoa, Lang Son and Cao Bang Provinces. I personally found it at Hàm Yên district (Tuyên Quang Prov.) - around the house of my mother-in-law ! - and at Cuu Thac-Tu Son (Hoa Binh Prov.). So clearly widespread and not rare.

Lamelligomphus camelus, a male assuming the obelisk posture at midday

The commonest Lamelligomphus in northern Vietnam. This male has been photographed within the park boundaries.

Lamelligomphus camelus, male caudal appendages
Note the distinctive humps on S8, that gives this species its name. Note also the dorsal tooth at one third of the superiors and the protrusion of the tip of inferiors.

Orientogomphus naninus, male, taken from a small river (20 m wide) with moderate flows across agricultural land, with well-vegetated banks at some sections.

Orientogomphus naninus, male, face

Orientogomphus naninus, male, caudal append. (dorsal, lateral and ventral views)

Habitat of Orientogomphus naninus

(+ Peudagrion spencei in the grassy beds, Dysphaea basitincta, Burmagomphus cf. vermicularis on rocks)

Open stream, 15m wide, with gravel/rocks bottom substrate

The male Orientogomphus naninus was hovering at noon below the first trees on the left

Habitat of Lamelligomphus vietnamensis, Macromia clio, M. cupricincta and Dysphaea basitincta

An open aspect, gravelly bottomed river, with moderate flows running across hilly landscape covered with tea plantations. L. vietnamensis were hovering above the small gravelly rapids in the centre of the image, M. clio were cruising along the beds (quite long distances), M. cupricincta was caught above the puddle in the left (patrolling back and forth short distances) and D. basitincta was perched conspicuously on the banks vegetation.

Macromia clio, male

My 7th Macromia species

Macromia clio, male

Blackish face and white postclypeus

Macromia clio, male
Note the yellow labium. Viewed ventrally, it appears broadly edged in yellow

Macromia clio, male, caudal append. (dorsal and lateral views)

Macromia cupricincta

Found this species in June at Mê Linh-Tam Dao along a 1,5m wide stream (see my precedent post)

Macromia cupricincta - same individual after capture
Note the reddish face, the extreme curve of the wing at the anal triangle, indicative of this species, and the spike on the dorsum of S10

Macromia cupricincta

Macromia cupricincta, male, tip of abdomen in lateral view

Dysphaea basitincta, male – originally described from “Tonkin” (i.e. northern Vietnam)

Found at almost all river stretches I checked. Perched on rocks/fallen branches in the middle of the river or on the overhanging bank vegetation

Another male

Dysphaea basitincta, wings close-up
The base and apex are black and opaque in both wings, the intermediate are being hyaline

Pseudagrion spencei, male

Encountered in the grassy banks of broad open aspect streams and rivers and in the nearby rice fields

Pseudagrion spencei, copula
Smaller than P. microcephalum and P. australasiae, different ocular spots, different caudal appendages, greenish wash along the abdomen in the male. The female is also very plain, very different from the ones of microcephalum and australasiae

Pseudagrion spencei, female

Mnais mneme, orange-winged male

Few individuals encountered. The season is almost over for this spring species. Better no to use flash with the pruinosed individuals, if not it can really alter their appearance.

Mnais mneme, male

Vestalis gracilis, male
Better not to use flash for this one also

Vestalis gracilis, female

Archineura hetaerinoides, female

Not the easiest Calopterygid species to photograph. I'm constantly frustrated by their refusal to allow close approach. 80-90 % of the individual are very alert, but sometimes you bump into a tame one which allow a very close approach, as you can see from my photos.

Archineura hetaerinoides, female

Phaenandrogomphus tonkinicus

An expert hovering Gomphid !

Habitat of Phaenandrogomphus tonkinicus

and Chlorogompus sachiyoae

Ch. sachiyoae was patrolling back and forth short distance (ca 20m) along the banks

Chlorogompus sachiyoae, male
Some males were observed (and caught for identification) making slow patrolling flights up and down the stream course, at a height of 0.1m to 0.3m above the stream.

The only Chlorogomphus species recorded at Xuan Son so far. Seems to be the most successful Chlorogomphus in northern Vietnam – recorded in many localities, in lowland and mountains. Bust just a few years ago, only known from the type locality (Tam Dao)!