The Society for the study of flies (Diptera)

Renko · 2020-02-17 00:07:57

Could you help me with these Anthomyiidae found in North of France, at Bonningues-les-Ardres, in a deciduous forest composed of mainly Fagus sylvatica, in an undergrowth with Rubus sp. and many ferns ?
I recolted many galls from an unknown species of ferns, the 22 Mai 2018, the galls were very similar to the one of Chirosia betuleti. Unfortunately, I lost the pictures of the galls and the larvae.
Some adults have emerged the 10 april 2019 (maybe a bit soon in the season), I first thought it was Chirosia betuleti but somebody proposed me Chirosia crassiseta due to the shape of the arista. But I am not entirely sure. It is possible to say anything from these pictures ?

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Michael Ackland · 2020-02-17 14:53:25

I can't say what species it from the photos, but it is not Chirosia crassiseta, which has in the male the eyes widely separated, as in this extract from my key:
11 Eyes widely separated, frons 2.5�3 times width of postpedicel. Katepisternal setae 1 + 1,
no differentiated lower posterior seta. Head viewed from a low angle in front with frontal
vitta more than twice as wide as a parafacial, both equally grey dusted. Parafrontal angle
in lateral view rather projecting in front of level of receding lower facial edge,
postpedicel rather large, arista short and swollen in basal half........................................
.................................................................................................................crassiseta Stein

Renko · 2020-02-18 18:35:21

Thanks you very much, Michael for your complete and precise reply !

The Society for the study of flies (Diptera)

#1 2020-02-17 00:07:57

Anthomyiidae, Chirosia

#2 2020-02-17 14:53:25

Re: Anthomyiidae, Chirosia

#3 2020-02-18 18:35:21

Re: Anthomyiidae, Chirosia

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