Schwimmen bei der Wasserwespen-Art Prestwichia aquatica (Hymenoptera: Trichogrammatidae)

Diving wasps, Prestwichia aquatica Lubbock 1864, were videorecorded in a flat micro-aquarium under a dissecting microscope. Records were analyzed frame by frame. P aquatica of 0.9 mm body size swims with the aid of legs with 5-7 mm/s, striking about 7 cycles per second. Walking on the dry ground or underwater, it advances 2.8-3.5 mm/s, stepping about 2.6 cycles per second. Leg co-ordination in swimming as well as in walking is of the alternating tripod type. Trajectories of the swimming power stroke in the middle and hind legs are spaced.