My Russian friends say this is probably a Sphinx (hawkmoth) family, that really only narrows it down a little.
Some hawk moths, like the hummingbird hawk moth, hover in midair while they feed on nectar from flowers and are sometimes mistaken for hummingbirds. This hovering capability has evolved only three times in nectar feeders: in hummingbirds, certain bats, and these sphingids.
an example of convergent evolution ....if you know what that is :-) That's the 'Looks like a Duck Quacks like a Duck, swims like a Duck but is not
a Duck theory.