Thermoregulation and the effect of body temperature on call temporal parameters in the cicada Diceroprocta olympusa (Homoptera : Cicadidae)

We investigated the thermoregulatory behavior, thermal responses (minimum f light, maximum voluntary tolerance and heat torpor temperatures) and the ef fect of body temperature (T-b) on call parameters in the cicada Diceroproct a olympusa (Walker). Regression of T-b as a function of ambient (T-a) or pe rch temperatures (T-p) suggests thermoregulation is occurring. Thermoregula tion occurs through behavioral changes that alter the uptake of solar radia tion. T-p is a better predictor of T-b than is T-a. Thermal responses (mini mum flight temperature 20.4 degrees C, maximum voluntary tolerance temperat ure 37 degrees C, and heat torpor temperature 46.7 degrees C) may be relate d to the humid, grassland habitat of the species. in contrast to other acou stic insects, no significant relationship was found between the temporal pa rameters of the calling song and T-b within the population of D. olympusa. (C) 2000 Elsevier Science Inc. All rights reserved.