Diptera.info

Posted by Graeme Cocks on 29-08-2015 20:43

I believe this is Tachinidae, but the arista are plumose? Probably Dexiinae. Are there genera that have plumose arista in this subfamily? Malaise trap. Townsville, Queensland.

Posted by John Carr on 29-08-2015 22:43

In North America the defining characters of tribe Dexiini are

* Only one frontal bristle arising below upper margin of pedicel
* Pedicel with one or two exceptionally long slender setae which are more than half as long as arista
* Arista pubescent or plumose
* Subvibrissal ridge with five or more slender bristles usually continuous with bristles of subcranial margin.

See Manual of Nearctic Diptera page 1247. No doubt there are a few exceptions. The plumose arista alone will usually work.

In addition, Dexiini and Siphona account for most of the long-beaked Tachinidae in the Northern Hemisphere. (At least, most of the ones photographed.)

Posted by Graeme Cocks on 29-08-2015 23:01

Thanks John. There is one listed on ALA, Siphona kairiensis, but there is no picture.
So I will go with your suggestion as Siphona sp. as a possibility.

Posted by John Carr on 29-08-2015 23:03

Graeme Cocks wrote:
Thanks John. There is one listed on ALA, Siphona kairiensis, but there is no picture.
So I will go with your suggestion as Siphona sp. as a possibility.

It is not a Siphona. That is the other group to consider when you see a long-beaked Tachinidae. This looks like a typical Dexiini. I think your others were called Prosena.