Temperature-dependent Functional Response of the Arboreal Rove Beetle, Oligota flavicornis (Coleoptera: Staphylinidae), a Voracious Predator of Tetranychus urticae (Acarina: Tetranychidae).

Abstract

The functional responses of Oligota flavicornis (Boisduval & Lacordaire) (Coleoptera: Staphylinidae) preying on the eggs of Tetranychus urticae Koch (Acarina: Tetranychidae) were examined at seven constant temperature settings (12, 15, 18, 22, 25, 30, and 32°C) to elucidate the predator-prey interactions between them. Logistic regression showed that O. flavicornis exhibited type II functional responses to T. urticae eggs at different temperatures. The reciprocal of handling time declined exponentially with warming, and the search rate presented a single hump-shaped relationship with temperature. For the search rate, the lower temperature thresholds were 9.1°C (linear) and 8.7°C (Briere). The optimal temperature and upper temperature threshold were 29.1 and 37.8°C for Logan and 29.7 and 35.8°C for Briere, respectively. The predation threshold window of O. flavicornis reached 27.1°C with a range of 8.7-35.8°C. The predator could consume 244.7-388.4 T. urticae eggs in a day in the optimal temperature range (18-32°C). The voracious predatory behavior of O. flavicornis against T. urticae eggs over a broad temperature range indicates that the predator shows promise as a potential biological control agent and that temperature-dependent predation could be a basis for formulating strategies to control tetranychid mites.