Tonic immobility in adult Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) evoked by mechanical and optical stimuli

• Main Authors: Luule METSPALU, Aare KUUSIK, Külli HIIESAAR, Urmas TARTES
• Format: Article
• Language: English
• Published: Institute of Entomology, Biology Centre, Czech Academy of Science 2002-06-01
• Series: European Journal of Entomology
• Subjects: tonic immobility; gas exchange; body movements; heartbeats; colorado potato beetle; leptinotarsa decemlineata
• Online Access: https://www.eje.cz/artkey/eje-200202-0010_Tonic_immobility_in_adult_Colorado_potato_beetle_Leptinotarsa_decemlineata_Coleoptera_Chrysomelidae_evoked.php

Adults of Colorado potato beetle Leptinotarsa decemlineata are very active at room temperature, and their almost continuous struggling in the respirometer prevents the measurements of the patterns of gas exchange, body movements and heartbeat. The tonic immobility of beetles was evoked by light flashes and by shaking as external stimuli. The immediate reaction to these stimuli was the reflexive closing of the spiracles and the cessation of CO2 release for some minutes, which was followed by a large burst of this gas. The state of the evoked tonic immobility did not influence heartbeat and abdominal pulsations, but the periodically -occurring abdominal-thoracic pumping movements stopped for 2-5 minutes. During the periods of pumping ventilation the metabolic rate was increased about two times.The state of tonic immobility evoked by light flashes lasted 2-6 minutes, but when shaking was applied as a stimulus complete immobility was about two times longer.