Heat production in Littorina saxatilis Olivi and Littorina neritoides L. (gastropoda: Prosobranchia) during an experimental exposure to air

摘要: The adaptation of littorinid molluscs to prolonged aerial exposure was investigated by the determination heat production.Littorina saxatilis, inhabiting upper eulittoral, reached a maximum metabolic activity during submersion (heat production: 3.26×10−3J s−1 (gadw)−1. On first three days desiccation, production continuously reduced 40% submersed value. A lethal for this species. In supralittoralL. neritoides, stages energy metabolism could be observed: An intermediate (1.97×10−3Js−1 (gadw)−1), an increased hour 204% value), and minimal (39% value 19% value) following weeks desiccation. Recovery depended on water salinity;L. saxatilis proved less euryhaline thanL. neritoides. Thus, adaptations correlate with level littoral habitat; inactivity combined drastically consumption is metabolically economic way survive in periodically dry environments.