Just in time? Flexibility in reproductive traits of Vertigo antivertigo (Gastropoda: Vertiginidae) according to population origin, hibernation characteristics, and photoperiod

This study investigates the reproductive traits of Vertigo antivertigo, focusing on oviposition timing and number of eggs laid across varying environmental conditions to evaluate the species’ phenotypic responsiveness and adaptive capacity. Five experiments were conducted using snails from both geographically proximate and distant populations to assess the flexibility of reproductive traits in response to ecological factors such as habitat quality, hibernation conditions, and photoperiod. Significant inter- and intrapopulation differences were observed in response to microhabitat and hibernation conditions. Naturally hibernating snails initiated egg laying earlier and produced more eggs than those hibernating under laboratory conditions. Geographically distant populations differed in reproductive timing under laboratory conditions, suggesting local adaptation to seasonal constraints. Hibernation duration affected the onset of reproduction, supporting the role of endogenous rhythms in seasonal reproductive regulation. In contrast, photoperiod had no significant effect. Overall, the results highlight substantial phenotypic flexibility in reproductive traits of V. antivertigo, shaped by both passive environmental responses and adaptive processes, which may enhance resilience to ongoing climate change.