A male wasp from the Trypoxylon genus, Trypoxylon figulus.
This genus is reconizable from the thin and long first abdomen segment. These wasp hunt for spiders that are stored in the nest as food for the larvae. They nest in the bee hotel and use a mud plug to close the nest entrance and make walls between the nest cells.
Literature
1 Peeters, T.M.J., C. van Achterberg, W.R.B. Heitmans, W.F. Klein, V. Lefeber, A.J. van Loon, A.A. Mabelis, H. Nieuwen-huijsen, M. Reemer, J. de Rond, J. Smit, H.H.W. Velthuis, 2004. De wespen en mieren van Nederland (Hymenoptera: Aculeata). – Nederlandse Fauna 6. Nationaal Natuurhistorisch Museum Naturalis, Leiden, knnv Uitgeverij, Utrecht & European Invertebrate Survey – Nederland, Leiden.2 Breugel, P. van., 2014. Gasten van bijenhotels. – EIS Kenniscentrum Insecten en andere ongewervelden & Naturalis Biodiversity Center, Leiden.