FLIGHTLESSNESS AND RAPID TERRESTRIAL LOCOMOTION IN TIGER BEETLES OF THE CICINDELA L-SUBGENUS VANNIDEK,RIVACINDELA FROM SALINE HABITATS OF AUSTRALIA (COLEOPTERA, CICINDELIDAE)

Tiger beetles of the genus Cicindela L. subgenus Rivacindela van Nidek from saline habitats of Australia display great variation in locomoto ry behavior. A total of 30 species have been described, nine of which are flightless. A notable consequence of brachyptery in Rivacindela is the evolution of very rapid terrestrial locomotion. Brachypterous bee tles reach significantly higher cursorial velocities than macropterous ones. The running speeds attained by flightless Rivacindela are the f astest ever recorded for insects. The large species, Cicindela hudsoni Sumlin, reaches a maximal speed of 2.5 m.s-1, whereas the small-sized Cicindela eburneola Sumlin, attains the remarkable relative velocity of 170 body length.s-1. The evolution of flightlessness in Australian Cicindela occurred only in Rivacindela species and in Cicindela (Macfa rlandia) arachnoides Sumlin, a mimic of lycosid spiders. Correlation b etween flightlessness and stable and isolated habitats is noted and di scussed.