Hi all,
I pictured this female in Belgium around Huy on 2020-05-04.
It seems to be Platycheirus !
ObsIdentify we use in Belgium tells me it is P. albimanus but looking at the keys I read that in the P. albimanus group, if the 3d antenna's segment is orange below, it's Platycheirus sticticus
Here are some pictures I uploaded :