Present address: Department of Zoology, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
Adaptive significance of the recurrent photoperiodic response in a spring-breeding carabid beetle, Carabus yaconinus
Article first published online: 15 OCT 2010
© 2010 The Entomological Society of Japan
Volume 13, Issue 4, pages 367–374, December 2010
How to Cite
SHINTANI, Y. and NUMATA, H. (2010), Adaptive significance of the recurrent photoperiodic response in a spring-breeding carabid beetle, Carabus yaconinus. Entomological Science, 13: 367–374. doi: 10.1111/j.1479-8298.2010.00403.x
- Issue published online: 28 DEC 2010
- Article first published online: 15 OCT 2010
- Received 19 August 2009; accepted 16 May 2010.
- life cycle;
- photoperiodic sensitivity;
- reproductive diapause;
- seasonal adaptation
Seasonal changes in the photoperiodic sensitivity for reproduction in adults of a spring-breeding carabid beetle, Carabus yaconinus (Coleoptera: Carabidae), were examined by transferring adults from outdoor to photoperiodic conditions in various seasons. Newly-emerged adults transferred to the laboratory in September to December showed a long-day photoperiodic response, but lost photoperiodic sensitivity gradually during winter. In late April, overwintered adults were not sensitive to the photoperiod, with females continuing to have mature eggs under both long-day and short-day conditions. In contrast, in late June and late July, the adults were sensitive to the photoperiod, with only those kept under short-day conditions re-entering reproductive diapause. This recovery of photoperiodic sensitivity appears to play a definitive role in maintenance of diapause in autumn for adults that have reproduced. The adults collected in late April regained photoperiodic sensitivity in two months even after being kept under unchanged conditions. Therefore, no environmental cue is required for recovery of photoperiodic sensitivity, which apparently recovers with the lapse of time. Our results suggest that the recurrent photoperiodic response is required in long-living adults of C. yaconinus to regulate the timing of reproduction, and also indicate a difference in photoperiodic sensitivity in summer between overwintered and newly-emerged adults.