Diurnal activity, temperature responses and endothermy in three South American cicadas (Homoptera: Cicadidae: Dorisiana bonaerensis, Quesada gigas, and Fidicina mannifera

Abstract-l. Measurements of body temperature (r,) in the field demonstrated that endothermic icadas regulate r, by behavioral mechanisms as well as by endogenous heat production. 2. The Tb of endothermically active cicadas without access to exogenous heat is approximately the same as the Tb of basking cicadas. 3. Dorisiana bonaerensis (Berg) and Quesada gigas (Olivier) raise Tb in the field with the heat produced in flight. 4. The thermal responses of a particular species are related to its activity patterns and habitat. 5. Endothermy in cicadas may serve to uncouple reproductive behavior from environmental constraints; to circumvent possible thermoregulatory problems; to permit the utilization of habitats unavailable to strictly ectothermic cicadas; to reduce predation; and to optimize broadcast coverage and sound transmission