The selective action of different thermal ranges on two geographically isolated Asellus aquaticus (L.) populations (Holland and Southern Italy) is evaluated. Tolerance for high temperature (30°C) in individuals of the same population is inversely related to body-size. In addition, in both populations males exhibit a higher mortality than females, which have a consistently smaller size. In the southern population many individuals complete their biological cycle, whereas in the norther populations (from Holland) an extensive mortality is observed in all developmental stages.
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Con il contributo del Ministero per i Beni e le Attività Culturali