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3. What genus this mayfly ?

Dear community, thanks for consideridering these pictures.My cinpression is to be in front of a Rhithrogena, however I am not sure whether to classify it as Rhithrogena, Heptagenia or even Electrongena.
Along with the pics, additional info: I come across it in Italy, pre-alpine area, starting end of March or April. Size is around 2 or 2,5 cm., including cerci. The males are smaller.
Pic 1 the whole
Pic 2 the front leg
Pic 3 the rear leg

Thanks for any suggestions

regards
Andrea

Andrea-

Can I assume your specimen had only two tails, given that the genera possibilities you are considering are all of family Heptageniidae.

It would help to know how long in mm it was, exclusive of tails. One could estimate that, given the measure you provided, but for the fact that tail ends don't show in "the whole" photo.

It would also help to know which Italian region it was from. See Italian regions map below:

Hello Roger
the mayfly body measured 12 mm. without tails.
The region is Piedmont, the north part, close to the border with Aosta Valley.
I attach a picture of the ventral view of a female, unforunately the male flew away before I could portay it

Andrea

Andrea-

I would tend to favor Heptagenia because of the wing venation, and possibly H. longicauda because of the dark tarsi. However, this is just a guess at best.

Hi Roger,

I had thought that too, however some literature reports that in the rear foot, the tarsus 1 is longer then tarsus 3 in the Rhithrogena whereas in the Heptagenia Tarsus 1 is