Influência da umidad do substrato sobre crescimento, produ??o de ovos e sobrevivência de Bulimulus tenuissimus (d’Orbigny, 1835) (Mollusca, Bulimulidae) sob condi??es de laboratório.

摘要

Th life cycle of terrestrial snails is highly influenced by abiotic factors, including moisture. The aim of this study was to observe the effect of substrate moisture on the growth, fecundity, and survival of Bulimulus tenuissimus. For this study, 120 newly hatched snails (groups of 20 animals each) were subjected to three different levels of moisture of a substrate, over a period of 210 days. The reduction of substrate moisture caused a reduction in fecundity and survival of the snails, but it did not affect the growth. Land snails loose water through their skin and by the same means they rehydrate by being in contact with water. So, the moisture level of the substrate they touch directly influences the homeostasis of the snails. Thus, the dry substrate probably made rehydration difficult, which is essential to the maintenance of physiological and behavioral conditions that directly influence the parameters evaluated in this study.