Populations of Schizotetranychus brevisetosus Ehara (Acari: Tetranychidae), which live on the evergreen oak (Quercus glauca), survive the coldest months as either adult females or winter eggs. Adult females comprise the majority of the population in early November and oviposit from late November to early March. Most winter eggs hatch by late March, and adults of the next generation emerge in April. This species is considered an egg-diapausing species, but the environmental cues that regulate female reproductive arrest and resumption are mostly unknown. We investigated the photoperiodic responses of autumn reproductive arrest in 10 populations collected from different elevations in Shikoku, Japan. All populations showed long-day responses to critical daylength (CDL) around 12.2 h light (12.2L) at 20 °C, though there was no linear relationship between CDL and altitude. This result explains the steep decline in the proportion of summer eggs in November. Nonreproductive females developed under 10L at 20 °C commenced oviposition 14.3–20.6 days after transferring to 15L. This long pre-oviposition period explains the reduction in eggs before winter reproduction and suggests shallow adult diapause. Eggs thus obtained hatched in 12.9–15.3 days, similarly to summer eggs. Therefore, egg diapause in S. brevisetosus is much shallower than in species on deciduous hosts, which lay their winter eggs in early autumn to hatch at leaf flush in spring. The reproductive arrest and short hatching period may be an adaptation allowing egg-laying in midwinter, when predation pressure is low.

Schizotetranychus brevisetosus Ehara（Acari：Tetranychidae）的种群，生活在常绿橡树（Quercus glauca)，作为成年雌性或冬卵在最冷的月份存活下来。成年女性在 11 月初占人口的大多数，并在 11 月底至 3 月初排卵。大多数冬季卵在 3 月下旬孵化，下一代成虫在 4 月出现。该物种被认为是一种卵滞育物种，但调节雌性生殖停止和恢复的环境线索大多未知。我们调查了从日本四国不同海拔收集的 10 个种群中秋季生殖停滞的光周期反应。所有种群在 20 °C 下对 12.2 小时光照 (12.2L) 左右的临界日长 (CDL) 均表现出长日照反应，尽管 CDL 与海拔高度之间没有线性关系。这一结果解释了 11 月份夏季鸡蛋比例急剧下降的原因。在 20°C 下发育在 10L 以下的非生殖雌性在转移到 15L 后 14.3-20.6 天开始产卵。这个漫长的产卵前时期解释了冬季繁殖前卵子的减少，并表明成虫的滞育较浅。这样获得的鸡蛋在 12.9-15.3 天内孵化，类似于夏季鸡蛋。因此，鸡蛋滞育在S. brevisetosus比落叶寄主的物种浅得多，落叶寄主在早秋产卵，春季在叶齐平时孵化。繁殖停滞和孵化期短可能是一种适应，允许在捕食压力低的隆冬产卵。