Petaliaeschna tomokunii - the other Petaliaeschna

Haruki Karube described Petaliaeschna tomokunii in 2000 from Pia Oac in Cao Bang Province. Superficially this is a species very similar to P. flavipes. Indeed, it is easily overlooked as this species. I had observed P. flavipes both in Yen Bai Province and at Pia Oac. This year I carefully checked specimens at these sites and found that P. tomokunii flies at exactly the same places, although it appears to prefer the late afternoon, rather than the evening. I caught them both at Pia Oac and at Yen Bai patrolling over puddles on trails. In hand they are basically similar to P. flavipes, but the male has pointed rather than blunt appendages, making it easy to identify in hand. There luckily is another difference. P. tomokunii has the complete face and frons yellow-orange. In P. flavipes the upper edge of the antefrons is darker and the postfrons has a vague dark T-spot. This allows the females to be separated in hand too.
This is a spring species, like P. flavipes. I observed it between May 14 and June 29.

Male of Petaliaeschna tomokunii. Very similar to P. flavipes

But the appendages are quite different, both in dorsal view, as here, and in lateral view (see below). They are decidedly pointed.

This is the lateral view (not so sharp, sorry) 

And this is the all-yellow face and frons

A scan of a female in dorsal view, showing the unmarked frons

Petaliaeschna flavipes - a study in yellow

May 10 I eventually decided to stay at Nha Hang Khan Pha in Yen Bai. By the side of this inn a track goes into the woods along a stream. A perfect dragonfly place. It was a cloudy afternoon and to my surprise I found several aeschnids hunting low over the path or patrolling. Later on, towards dusk, there were many, flying about like Gynacantha. I was able to catch a female that had come out of the solitude of the bushes to catch a white moth, hence the white stuff on her face, and a male patrolling. The female had a fantastic deep ovipositor and the male and female both were strangely yellow, with bright yellow legs. Based on wing venation it should be something like Petaliaeschna or Periaeschna. In fact, it was Petaliaeschna flavipes, described from Northern Vietnam by Karube in 1999. It can be identified based on the shape of the appendages from several closely allied species.

Petaliaeschna flavipes, male

Petaliaeschna flavipes, female

Female (left) and male (right) in dorsal view

Appendages of male in dorsal view

In lateral view

And in ventral view

The weird shaped ovipositor of the female. No, this is not due to compression!