Thread subject: Diptera.info :: Agromyzidae - Phytobia sp.

Posted by Walther Gritsch on 18-01-2018 01:19
#1

My question concerns the identity of the species Phytobia betulae. I regularly find these large agromyzids in my malaise trap in a birch forest not far from Copenhagen.
When I dissect I normally have no difficulty in placing them in Phytobia cambii, but the one on the left hand side of the image looks much more like Phytobia betulae in Spencer 1976 (Fauna Entomologica Scandinavica). Now, is Ph. betulae a good species or are the differences in the aedeagus just a matter of point of view? In the photo I've made the aedeagusses are definately shown from different angles, but nevertheless they don't look exactly the same. The one on the right should be cambii ...
According to Fauna Europaea it seems the two species have been synonymized. What is the current state of affairs?

The specimens are from June 2016 og 2017.

Posted by mcerny on 18-01-2018 17:43
#2

Phb.cambii je valid name, von Tschirnhaus (1992) and Zlobin (2008) established synonymy of Phb. betulae with Phb. cambii (see Papp, Černý 2016: Agromyzidae (Diptera) of Hungary, Vol. 2). Phallus is variable and also it depends on angle view.
Milos

Posted by Walther Gritsch on 18-01-2018 23:24
#3

Thank you very much, Milos. I suspected it was just a matter of different angles. But nice to get it confirmed.