I found this for me unknown insect in my bee hotel photo backlog, and suspected it was a digger wasp species. Which it isn’t… but before I arrived at that conclusion I had already spend a full afternoon wrestling with a diggerwasp key which did not produce correct results… duh! 😂 So brute-force Google it is and voilà … a Masked bee, the Common Yellow Face Bee (Hylaeus communis)[1, 2].
She nests in bee hotels. This species is quit similar to Hyaline spatulate-masked bee (Hylaeus hyalinatus) but that species has,among other characteristics, longer cheeks (the line starting from the lower eye to the jaw)1.
References1 Peeters, T.M.J., H. Nieuwenhuijsen, J. Smit, F. van der Meer, I.P. Raemakers, W.R.B. Heitmans, C. van Achterberg, M. Kwak, A.J. Loonstra, J. de Rond, M. Roos & M. Reemer 2012. De Nederlands bijen (Hymennoptera: Apidae s.l.). - Natuur van Nederland 11, Naturalis Biodiversity Center & European Invertebrate Survey - Nederland, Leiden.
2 Hans Nieuwenhuijsen, Ivo Raemakers, "Tabel voor de bijen van het genus Hylaeus in Nederland", Nieuwsbrief Sectie Hymenoptera NEV – nr. 29, april 2009