Role of the compound eye and ocellus in photoperiodism

本研究旨在探讨复眼和单眼的光感受在光周期中的作用。一项手术摘除复眼的实验表明，普通Armadillidium vulgare的复眼参与了光周期性。光周期的敏感性是通过切除茎而丧失的。但手术后死亡率高，昆虫数量不足以下结论，复眼在日本小蠊和路氏花盲蝽寄生中的作用尚不清楚。在Plautia crossota stali中，复眼在光周期中起主要作用，尽管复眼以外的光感受器也可以接收光信息以实现光周期。此外，暗带双头线虫Dianemobiusnigrofasciatus和地原层虫Protophormiaterraenoprostus也同时利用视网膜外光感受器和复眼，以诱导昼夜活动节律，因此，视网膜外光感受器在脑内分布广泛，复眼是光周期的主要感光器，视物种而定，视网膜外受体或两种类型的光感受器都是有效的。

The present study aims to examine the role of photoreception by the compound eyes and ocelli in photoperiodism. An experiment with surgical removal of the compound eyes suggested that in Armadillidium vulgare the compound eyes are involved in the photoperiodism. Larvae of Leptocarabus kumagaii lost the sensitivity to photoperiod by ablation of the stemmata. However, the mortality after operation was high and the number of insects was not enough for conclusion.The role of the compound eyes in nymphs of Blattela nipponica and Poecilocoris lewisi is still unclear. In Plautia crossota stali, the compound eyes play a major role in the photoperiodism, although photoreceptors other than the compound eyes can also receive photic information for photoperiodism. Furthermore, Dianemobius nigrofasciatus and Protophormia terraenovae, in which the compound eyes have been shown to be the principal photoreceptor for photoperiodism, used both extraretinal photoreceptors and compound eyes for its entrainment of the circadian activity rhythm.Therefore, it is suggested that extraretinal photoreceptors in the brain is widely distributed and that compound eyes, extraretinal receptors or both types of photoreceptor are operative depending on the species.