The latitudinal uniformity of the unique life history of Velia caprai (Heteroptera: Veliidae) and notes to the pre-overwintering period of selected water striders (Heteroptera: Gerridae)

Temperate water striders (Gerridae) overwinter as adults and die after spring reproduction. European water cricket Velia caprai (Veliidae) overwinters concurrently in egg and adult stage in Central Europe. This rare overwintering strategy goes with longevity ofthis species. Adults can survive two winters in Central Europe, unlike other semiaquatic bugs. Scandinavian populations of V. caprai and water striders Gerris lacustris and G. lateralis were examined at the beginning and end of September to determine their life histories. Both gerrids start to overwinter during September, females prior to males and macropterous individuals prior to brachypterous. All females of G. lacustris and G. lateralis enter reproductive diapause before winter. V. caprai overwinters in both adult and egg stage in Norway, and can probably survive two winters. Central European and Scandinavian populations of V. caprai share the same unusual way of overwintering and probably also the whole life history.