#4
Hello, Andrea!
brazz wrote:
i think Eristalinus  sepulcralis   the eyes are all  hairy,  in the E. aeneus are bare on lower half.
Many thanks! I have also read that 
E. aeneus is much rarer here and mainly living in salty areas.
 
#5
in northern europe E. aeneus is indeed confined to salty areas, coastal lagoons,... in southern europe E. aeneus is more common, also inland.