I know I've been neglecting this blog lately. But the truth is, I've been very busy!
I’m back in the field now, when the sun shines, and hope to make up for lost time a bit. Below are some of my best photos from recent trips in May and June along the foothills of Tam Dao (Tây Thiên and Mê Linh) and a bit of blurb.These trips yielded some new species to my ever-growing Tam Dao species list. The best were 3 Macromia species and Heliogomphus retroflexus, all captured along a stream at Mê Linh. Four new species for me along a single stream in secondary forest, very unexpected... I also spotted there Labrogomphus torvus, which might be the first record for Tam Dao.
At Tây Thiên I checked the spot of the extremely localized Rhinocypha orea (around the nunnery) and found 5 males.
Many species were buzzing around everywhere... but I am too lazy to write a list!
Many species were buzzing around everywhere... but I am too lazy to write a list!
This male Macromia katae was found patrolling up and down a short, well-shaded stretch of stream at Mê Linh, Tam Dao (mid-May). Like Macromia pinratani vietnamica or Macromia malleifera, flight slowly on a quite rectilinear trajectory.
Stretch of stream at Mê Linh where 4-5 males
of Macromia katae were seen at 2 different visits.
Stream of stony and gravel bed running through secondary forest, thickets and orchards, but with woody riparian corridor
well conserved. Dragonflies are well-known to be sensitive to light
conditions, with the species having a range of light conditions that they
prefer. When these conditions are changed, such as by human removal of the tree
canopy, the odonata assemblage changes accordingly, with forest species being
replaced by species preferring sunlit habitats. Riparian corridors help to maintain odonata assemblages,
even when the surrounding habitats are severely degraded – this is the case at
Mê Linh.
This species has been described from Hong Kong in 1993. It is so far only known from few localities within lowland secondary forest in China (Guangdong and Hainan) and Hong Kong, in Laos near the Vietnam border (Yokoi 2003), and now from Vietnam, and it has been assessed as Vulnerable by the IUCN Red List (Wilson 2013).
Macromia katae in hand
All Macromia species can not be reliably identified without capture and closer examination
Macromia katae, male, distinctive facial pattern
Macromia katae, male, caudal appendages, lateral and dorso-lateral views : note the spine-like process on S10
Another interesting Macromia species I found recently at Mê Linh is Macromia urania. It is much smaller than M. katae and its flight is quite erratic.
Note the expansion of S7-9 and the 2 dorsal spots on S8
Macromia urania, male, Mê Linh
Close-up on the male secondary genital apparatus
note the wavy outline of the hamule
Blackish face with yellow postclypeus
The third Macromia species I recorded at Mê
Linh is M. cupricincta. It was sharing with M. urania the same short, open stream stretch - at the difference of M. katae which was caught in a well-shaded stretch. These three Macromia species were active at midday.
Macromia cupricincta, male, Mê Linh
Described from India (1924), subsequently found in Malay Peninsula, Laos, Myanmar and Thailand. First record in Vietnam from the South (Karube, 2011), but also presence in the North as shown by this record and the one (the ones?) of Tom Kompier.
Identified as cupricincta based on the combination of brown-reddish face, extreme curve of the wing at the anal triangle and long acuminate spine on the dorsum of S10. Note also the coppery-brown wash on tip of abdomen, on S4-6 (ventral half).
Macromia cupricincta, male, caudal appendages, lateral view (left) / dorsal view of abdomen (right)
The 50m open stretch at Mê Linh where Macromia cupricincta and M. urania were caught.
Males Labrogomphus torvus were also spotted there, perched on stones. I was astonished by this spot (very ordinary, I always thought these species were a bit picky habitat-wise). These species where found nowhere else along the 700m of stream surveyed (4 times).
I also add here a fourth Macromia, a very common one this
one, photographed at Tây Thiên : Macromia pinratani vietnamica.
Macromia pinratani vietnamica, male, roosting 30m away from the water (Tây Thiên) A widespread and very common Macromia, but a roosting individual is quite a rare sight
Another male photographed at a greater distance with a 400 mm telephoto lens- the one I use for birds
Macromia pinratani vietnamica in flight when patrolling a small brook in forest.
Males consistently patrol a few dozen of centimeters above the water, slowly, on a rectilinear trajectory.
Rhinocypha orea, Tây Thiên, a typical view of a male perched few meters above the stream on leaves
I spotted 5 males Rhinocypha orea around the
nunnery in mid-May 2015, all detected in flight – the vibrant golden-colored
wings attract the eye. Described in 2011 from Tam Dao, this damselfly has never been recorded
elsewhere.
Rhinocypha orea, male, Tây Thiên
Rhinocypha orea, male, Tây Thiên
Forewings hyaline, hindwings with 2 different pattern : oustide black with green sheen at tip, inside golden and dark reddish at tip.
Euphaea masoni, female crawling down a
plant stem to get under the surface for submerged oviposition
Archineura hetaerinoides, male, Tây Thiên
Euphaea decorata, teneral male, Mê Linh
The exuvae it has just crawled out of
Lamelligomphus formosanus, Tây Thiên, a male obelisking at midday (to minimize solar radiation falling on it)
Ophiogomphus sinicus, male, Tây Tiên
Merogomphus paviei, male, Mê Linh
The first time I encountered this species at Tam Dao
Labrogomphus torvus, male, Mê Linh
A recent addition (2013, Huu Liên, Lang Son Prov.) to the Vietnamese fauna. According to Tom's blog, quite widespread in northern Vietnam, but certainly not common.
In 2012 near the Tam Dao Bear Rescue Center, I photographed an unknown gomphid which I identified 2 years later as Labrogomphus torvus. This new record confirm its presence within the massif.
Gomphidia kruegeri, male, Mê Linh
Gomphidia kruegeri, a male obelisking, Mê Linh
Gomphidia kruegeri, male, Mê Linh
Gomphidia abbotti, male, Mê Linh
Gomphidia abbotti, female, Mê Linh
Asiagomphus auricolor, male, Mê Linh
Asiagomphus auricolor, male, Mê Linh
Asiagomphus auricolor, male, Mê Linh
Asiagomphus auricolor, male, Mê Linh
A quite different pattern (less yellow on S1-2, complete humeral
stripe) but I could not find any structural differences
Philoganga vetusta, female, Tây Thiên
Philoganga vetusta, female, Tây Thiên
Tetracanthagyna waterhousei, female, Mê Linh
This common Aeshnid prefers well-shaded stream with steep banks
This common Aeshnid prefers well-shaded stream with steep banks
Macromidia rapida, female, Mê Linh
A rather common species at the foothills of Tam Dao.
Macromidia rapida, female, Mê Linh
Macromidia rapida, female, Mê Linh
Tetrathemis platyptera, male, Tây Thiên
Trithemis aurora, male, Tây Thiên
Cratillea lineata, male, Tây Thiên
I feel that, every now and again, it’s worth taking a moment
to pause and ponder how beautiful the world around us is. Scenes like
this:
Zygonyx iris, male, Mê Linh
… really help me center myself and relax. That might be a very common dragonfly, one that I see throughout the season in my area, but the sight of them never grows old.
They remind me how amazing our world is, and how many things
I’ve yet to experience. Do any of you get the same feeling in nature?
Zygonyx iris, male, Mê Linh
Onychothemis testacea tonkinensis, male, Mê Linh
Onychothemis testacea tonkinensis, male, Mê Linh
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