Zum Fortpflanzungsmodus fossiler Kleinlibellen (Insecta, Odonata, Zygoptera)

Fossil egg-sets of damselflies (Insecta, Odonata, Zygoptera) are recognized from well known localities such as Randecker Maar, Messel (both in Germany) and in an old record about sediments from the Upper Cretaceous of Bohemia (Czech Republic). Such finds bearing witness to the behaviour of certain fossil insects are extremely rare, especially in stratified sediments. Hitherto they have only been recorded from the Upper Oligocene Fossillagerstatte Rott near Bonn (Germany). Two different types of egg-sets could be distinguished; they were described and figured byHellmund &Hellmund (1991, 1993). It is striking that the gap between finds from the Upper Oligocene and those from modern times is mainly due to insufficient observations. The explained strategy of reproduction obviously evolved at least 95 m.a. ago and has been practiced unchanged today.