After looking further into these Euchromius, I will reluctantly disagree with vinculellus.
I don't have the corresponding volume of Microlepidoptera Palaearctica, so I don't know which similar non-European species there are.
I have Slamka (PoE 2) in front of me, and:
- Forewing of vinculellus are stated there to have 6-7 black spots, while my moth (3 specimens collected, which all look alike) has at least 8.
- Forewing is supposed to be slender in vinculellus, my moths have quite wide, triangular forewings.
To me it looks more like E. superbellus for now. Hopefully I hold the specimens, although I don't know when I'll dissect them (I already have 3 freezers of insects on cotton wool mattresses)...