Bayadera and Dysphaea

During my trip to Cao Bang Province and from there westward, I ran into an unknown (to me) robust Bayadera perched at a small stream coming from the woods by the road side on June 30 in western Cao Bang Province. It had a dorsal tooth on the superior appendages, something immediately drawing attention. Subsequently, I found out there are two species that share this characteristic: Bayadera serrata, described in 1996 by Davies & Yang from China, and Bayadera kinnara, described recently by Hamalainen from Burma. Based on the shape of the appendages my Bayadera could be identified as B. serrata. This is not the first time the species is reported from northern Vietnam, but records are scarce.

Bayadera serrata, a nice male

Head and thorax up close

The distinctive appendages. Note the dorsal tooth to the superior appendages

Note the serrated edge to the superiors.

Another Bayadera I ran into was Bayadera hyalina, but I saw it only once, which was rather surprising. Two males perched on rocks in the middle of a stream near Sa Pa.

A fine but distant male Bayadera hyalina

Also in Cao Bang Province on June 30 I noticed at the end of the day under a cloudy sky a Dysphaea perched high in a tree, far out of reach of my net, but not of my camera. It seemed to have all dark wings, something that was terribly confusing. I blamed it on the weather that it looked so dark. But the next morning and a swollen river due to the heavy rains of the night before I noticed two more all dark Dysphaea males. One sat in a bush overhanging the river close to the bridge from where I was watching and I judged I could get to it. So I moved into the churning waters, carefully judging whether I would be able to keep my footing. Close to the insect the waters were less deep and less turbulent and I got close enough to it to be able to net it. It tuned out to be Dysphaea haomiao, a species only recently (2011) described, by Hamalainen (thanks for the great work, Matti!).

The first observation, high up in a tree

And the second on July 1, male perched above the churning waters, Dysphaea haomiao.

The same male after capture. Note the many many mites happily sucking away on its belly!

See the horror in close-up, sschlup sschlup