Bayadera hatvan and Bayadera hyalina*

*This entry was adjusted on December 23. The ID was adjusted to B. hyalina. It was adjusted again in June 2015 upon publication of Bayadera hatvan.

On May 11 I was checking streams in Yen Bai. Twice I ran into a male Bayadera hyalina. I found them in shaded areas in surroundings with at least heavy shrub cover and rocks. This species was known from only a few localities, although it was thought to be more common. It was known from Thailand and India, but it had not been recorded from Vietnam. But I was very surprised when checking a large rather open stream to find another Bayadera sitting on branches fallen into the stream at the bottom of a cliff. This was a very distinctive species, with dark tips to the wing and in hand with broad superior appendage tips. Although very similar to Bayadera indica, closer inspection revealed that it was in fact different. Earlier claims of B. indica from China (Yunnan) may well refer to this new species, not to B. indica. The species was described in May 2015 by Hamalainen and Kompier as B. hatvan.

Male Bayadera hatvan

Female Bayadera hatvan

Male Bayadera hyalina

Another male in hand

Appendages of B. hyalina in ventral view

Compare ventral view of appendages of B. hatvan

Appendages of B. hyalina in ventral view

And the same for B. hatvan

And finally dorsal view appendages B. hyalina

And similarly, dorsal view appendages of B. hatvan