Wednesday, 15 November 2017

Gomphidictinus tongi, a wonderful discovery from Vietnam

In May 2016 I observed, but could not catch, a large Gomphidia-like gomphid in pristine forest just south of Phong Nha - Ke Bang National Park in Quang Binh Province in Central Vietnam. I thought it might have been Gomphidictinus kompieri, because of its deep forest habitat. I visited several times later in the season, but it rained every time and so I did not see it again. But this year I visited in early June and was more lucky. Not only did I catch a male, I also found the species next to the botanical garden of the National Park. And it clearly was not G. kompieri. It was a new species for sure, judging from the shape of the appendages, coloration and wing venation.

Not long after I was contacted by Zootaxa regarding a manuscript for a new Gomphidictinus species from China by Haomiao Zhang and colleagues. And what a surprise when this turned out to be exactly the same species: Gomphidictinus tongi Zhang, Guan & Wang, 2017. This lead to an interesting debate regarding its genus. Although the species is currently included in Gomphidictinus, in the same manner as G. kompieri was included in it, on the basis of the spine on the vesica spermalis, differentiating between Gomphidia and Gomphidictinus is not straightforward, not on the basis of this spine, nor on the basis of for instance wing venation. An overhaul of the genera, including DNA-analysis, is needed to solve this, but for now this fabulous dragon is included in Gomphidictinus as the third member of that genus.

Some unidentified Gomphidia / Gomphidictinus reported from Tam Dao by Natalia von Ellenrieder likely also concern this species, which therefore may be more widespread in Vietnam, apart from ranging widely in China (now recorded from Guangxi and Hainan). Interestingly, the two male specimens from Vietnam in below pictures indicate some variability in the maculation of the abdomen.

Female of Gomphidictinus tongi. It has wide flaps to S8, although not so visible here

Typical male showing already striking yellow markings compared to the two other species in the genus.

Slightly overexposed, so not as yellow, second male, but note extensive marking of S6 compared to the first.