【目的】 本研究以新疆荒漠昆虫哈氏东鳖甲Anatolica hammarstromi、洛氏脊漠甲Pterocoma loczyi以及卵形刺甲Platyscelis obovatus为对象，研究其成虫不同的昼夜活动以及产卵节律，获取24 h活动规律和产卵时刻数据，弥补这3种拟步甲在相关研究上不足的同时为其生物学特性等后续研究奠定基础。【方法】 在温度（30±0.5）℃，30%±6%的相对湿度，16 L∶8 D光周期的环境条件下，每隔1 h记录拟步甲成虫的活动率和对应的产卵数量比率，以记录一个完整的昼夜，共记录5 d，表征3种拟步甲昼夜活动以及产卵节律。【结果】 哈氏东鳖甲与洛氏脊漠甲成虫的活动及产卵行为均表现出明显的昼行偏好。哈氏东鳖甲白天活动占比为81.88%，夜晚仅占18.12%，昼夜活动差异极显著（P < 0.000 1），活动峰值出现在下午13∶58；其产卵行为同样集中在白天（占比92.08%），夜晚产卵比例仅为7.92%，昼夜产卵差异显著（P = 0.000 7），产卵高峰出现在下午14∶46。洛氏脊漠甲白天活动占比为74.59%，夜晚为25.41%，昼夜活动差异极显著（P < 0.000 1），活动高峰出现在下午15∶50；其白天产卵占比达83.68%，夜晚为16.32%，昼夜产卵差异显著（P = 0.011 5），产卵高峰出现在下午17∶33。与此相对，卵形刺甲成虫则具有夜行偏好。其白天活动占比为43.27%，夜晚为56.73%，昼夜活动差异极显著（P < 0.000 1），活动高峰出现在凌晨3∶35；产卵行为亦以夜间为主，白天产卵占比37.55%，夜晚达62.45%，昼夜产卵差异显著（P = 0.000 7），产卵高峰出现在凌晨00∶14。【结论】 3种拟步甲产卵与活动均表现出显著的昼夜节律，且节律相同步。其中哈氏东鳖甲与洛氏脊漠甲的活动与产卵行为均集中在白天，属于日行性昆虫；而卵形刺甲的活动与产卵则集中在夜晚，属于夜行性昆虫。

 [Aim]  To clarify differences in the 24-hour activity profiles and timing of oviposition in three darkling beetle species, Anatolica hammarstromi, Pterocoma loczyi, and Platyscelis obovatus, from the Xinjiang, thereby providing information useful for timing the collection of adult specimens and eggs. [Methods]  Under controlled environmental conditions of (30 ± 0.5) ℃, 30% ± 6% relative humidity, and a photoperiod of 16 L∶8 D, the number of active and ovipositing adults of each species were recorded hourly for an entire day over a 5 d period. [Results]  Adult A. hammarstromi and P. loczyi were predominantly diurnal. 78.70% of A. hammarstromi were active during the day compared to 21.30% at night, with peak activity occurring at 13∶58. 90.92% of all eggs laid were laid during daylight hours with the peak of oviposition occurred at 14∶46. 69.12% of P. loczyi were active during the day and 30.88% at night, with peak activity observed at 15∶50. Approximately 75.41% of the eggs of this species were laid during the day with the peak of oviposition occurring at 17∶33. In contrast, just 43.27% of P. obovatus were active during the day compared to 56.73% at night, with peak activity occurring at 3∶35. Just 37.55% of the eggs of this species were laid during the day compared to 62.45% at night, with the peak of oviposition occurring at 00∶14. [Conclusion]  All three species of darkling beetle had significantly different, closely synchronized, circadian rhythms in both oviposition and locomotor activity. A. hammarstromi and P. loczyi were both predominantly diurnal in both locomotor activity and oviposition, with 81.88% (P < 0.000 1) of A. hammarstromi and 74.59% of P. loczyi (P < 0.000 1) active during the day. 92.08% (P = 0.000 7) of the eggs of A. hammarstromi and 83.68% of the eggs of P. loczyi (P = 0.011 5) were laid during the day. In contrast, P. obovatus was mainly nocturnal, with 56.73% (P < 0.000 1) of adults active during the night and 62.45% (P = 0.000 7), of oviposition occurring at night.