Thread subject: Diptera.info :: Tachina fera or magnicornis?
Posted by Cor Zonneveld on 15-12-2008 18:47
#1
At a Dutch forum we had a discussion about this specimen. The head seems to be very wide, the tarsus of leg 1 brown, both suggestive of magnicornis. But...is it a male or female (how do you see this?)? Is a definitive ID possible?
Edited by Cor Zonneveld on 15-12-2008 20:58
Posted by Cor Zonneveld on 15-12-2008 18:49
#2
For comparison: this one has a smaller head, and more yellow tarsus of leg 1. Is this a sure T. fera?
Posted by Cor Zonneveld on 15-12-2008 19:10
#3
Here another picture of the first specimen, showing abdomen coloration (I know, not decisive...)
Posted by Cor Zonneveld on 15-12-2008 19:18
#4
and a frontal view, for head width
Posted by javanerkelens on 15-12-2008 20:29
#5
Dear Cor,
Indeed you placed this thread already on Waarneming.nl, and I thougt it was a T.magnicornis, and I hope it is, but I was curious , when there is a outer orbital seta present (and I think I see one on your photo) is it always a male T magnicornis ....or can it be also a female..?
Or are both female's T.fera + T.magnicornis whitout outer orbital setae...?
So when there is a outer orbital, you always can say it is a male T.magnicornis....????
Joke:)
Edited by javanerkelens on 15-12-2008 20:30
Posted by Zeegers on 15-12-2008 21:15
#6
Most females in Tachinidae have 2 pairs of proclinate orbitals seae present (there are exceptions of course), most males don't.
So the second pic is clearly a male T. fera.
The other ones are females and seem to be T. fera as well. However, females fera and magnicornis can be incredible similar and sometimes hardly impossible to separate.
Theo
Posted by javanerkelens on 15-12-2008 21:36
#7
most males don't.
Hmm... In a discription of Tschorsnig en Herting:
Males: anterior claws clearly shorter than the last 2 tarsal segments combined;
frons with 1 or 2 outer orbital bristles......then T.magnicornis.
Very confusing...for a amateur..:o
Joke;)
Posted by Cor Zonneveld on 15-12-2008 21:43
#8
OK, now I start to doubt about all my fera/magnicornis... What about this, a 'sure' magnicornis??
And thanks for your patience!
Posted by Zeegers on 16-12-2008 21:56
#9
To Joke: that's why I said 'most', I don't see the problem.
The male genitalia of Tachina are very large, so you can tell with you eyes closed if it is a male. And if it isn't, it is female.
To the last picture: IDing females Tachina from picture is never sure. But this really looks like magnicornis.
Theo
Posted by javanerkelens on 16-12-2008 23:03
#10
To Joke: that's why I said 'most', I don't see the problem.
The male genitalia of Tachina are very large, so you can tell with you eyes closed if it is a male. And if it isn't, it is female.
Next time, I wil close my eyes for a short time....:D
Joke