not in Young In the area of a clearing adjacent to a roadside in the vicinity of Mali Losinj, Croatia, 11 species of Hymenoptera spending the night attached on plants could be found during short stays in three successive years, namely: Anthophoridae: Eupavlovskia obscura (FRIESE), Melecta duodecimmaculata (Rossi), M. leucorhyncha GRIBODO, M. albifrons FORSTER, Nomada femora/is MORAWITZ, N. integra BRULLE, Anthophora dalmatica PEREZ; Andrenidae: Andrena ovatula KIRBY; Eumenidae: Odynerus melanocephalus (GMELIN); Scoliidae: Scolia hirta SCHRANK; Ichneumonidae: Syzeuctus fuscator (PANZER). Females of Anthophora subterranea GERMAR were observed staying over-night in their nests. Sleeping postures, attachment places and, for some specimens, the process of falling asleep or waking up are described. Hymenoptera (Insecta). Hymenoptera: Sleep, Croatia, Mali Losinj. Arthropods; Hymenopterans; Insects; Invertebrates. none2008checked