A lost guest in the house, a male Jet ant (Lasius fuliginosus) [1]. (det. RutgervH / P.Boer). The males of this species have antennae with 13 segments. The in ants characteristic nod in the antennae after the first antennal segment is missing in males [2], a character that I was not aware of and which initially caused me to think this was some vague wasp 😅


Literature
1 Nederlands Soortenregister2 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.