Thread subject: Diptera.info :: Psychoda grisescens - but aedaegus in reverse!

Posted by Louis Boumans on 16-10-2009 14:34
#1

I'm a newcomer in Psychodidae.. But I'm quite confident this Psychoda is grisescens. But the asymmetrical genitalia - aedagus is the mirror image of the drawings in Phil Withers' book and the original description by Tonnoir 1922.

I wonder what could be the explanation for this:
- an artefact in my picture through the binocular (I don't think so; I checked and experimented taking pictures of small print letters)
- mistake in Tonnoir, copied in Withers?
- real variation?
- I assume all pictures are from dorsal (= morphological ventral) side - could I be mistaken here?

Does anyone have a picture or specimen of another P. grisescens, or anotjher idea? I am confused..

Thanks, Louis

Edited by Louis Boumans on 16-10-2009 14:36

Posted by phil withers on 16-10-2009 17:55
#2

I suspect I mounted the specimen I drew upside down - especially as I always separate the upper and lower parts, this is easy to do (about half of the specimens in my collection look like that). This is definitely grisescens, as seen from the tiny teeth on the 9th sternite, and the shape of the aedeagus. Good photo...

Posted by Louis Boumans on 17-10-2009 01:38
#3

Ah Thanks for the confirmation of the identification! It's great to be in direct contact with THE Phil Withers who wrote the British identification key!

So far I kept all my Psychodidae in ethanol, so it didn't occur to me that it's actually equally logical to draw the genitalia from the ventral side. Checking once more Tonnoir's drawing I see that he states it in the caption: some species drawn "vu de dessus" some "vu de dessous" - hadn't noticed that!