European Journal of Entomology

      ISSN 1210-5759 (print), 1802-8829 (online)

Eur. J. Entomol. 2004, 101(3): 491–494  

Water loss of male and female Alphitobius diaperinus (Coleoptera: Tenebrionidae) maintained under dry conditions

RENAULT D.* & CORAY Y.

Survival under dry conditions was examined in males and females of Alphitobius diaperinus Panzer (Coleoptera: Tenebrionidae), a beetle of tropical origin. The range of individual responses and the effect of gender on water loss were also evaluated. Females exhibit significantly longer survival (Lt50 and Lt90) than males under desiccating conditions. Larger females beetles have a greater initial water mass and hence can tolerate greater water losses. Such beetles have longer survival under dry conditions. Males and females loose an average of 54.8 and 58.9% of their body water prior to death. The insects were inactive most of the time, when kept under dry conditions; the rate of decrease in body water was thus reduced. Beetles of both gender display a negative correlation between the rates of water loss under desiccating conditions and the duration of survival. We conclude that the difference in survival period between males and females is due to a combination of greater female tolerance to desiccation and larger body size.

Address
UMR 6553 CNRS, Université de Rennes 1, Station biologique, 35380 Paimpont, France; e-mail: renault.david@laposte.net

Keywords
Desiccation resistance, survival, sex, body size, body water, water loss rate, Tenebrionidae, Coleoptera

accepted: Apr 1st, 2004    published: Sep 20th, 2004    URL: http://www.eje.cz/scripts/viewabstract.php?abstract=726


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