Operational sex ratio and paternal age are known to independently affect mating behaviour and reproductive performance. We conducted experiments to assess the effects of operational sex ratio and paternal age on mating, reproduction, and total development duration of Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae). Three male-biased sex ratios, no (1:1), modest (1:2), and extreme (1:5) competition treatments, were formed using young, middle-aged, and old males. The reproductive performance of M. sexmaculatus at all ages under extreme competition (1:5) surpassed the other two treatments. More competition among males decreased the time of commencement of mating and increased the duration of copulation. Females laid a greater number of eggs in extreme competition treatments. The operational sex ratio (irrespective of age) had no significant effect on the total developmental duration of offspring. Among different age groups, older males took more time to commence mating and mated for longer durations in all the sex ratio treatments. The number of eggs in the first clutch was lowest when females were mated with older males with increased offspring development duration. Thus, it can be concluded that male-biased sex ratio elevates the performance of M. sexmaculatus. Among different age groups, older males were poor performers than young and middle-aged males.

已知工作性别比和父亲年龄独立影响交配行为和生殖能力。我们进行了实验，以评估工作性别比和父亲年龄对性对虾（Fabricius）（鞘翅目：球虫）的交配，繁殖和总发育时间的影响。使用年轻，中年和老年男性，形成了三种男性偏见的性别比例，即无（1：1），适度（1：2）和极端（1：5）竞争待遇。性斑母鼠的生殖性能在极端竞争下的所有年龄段（1：5）都超过了其他两种治疗方法。雄性之间的竞争加剧，减少了开始交配的时间，并延长了交配的时间。在极端竞争治疗中，雌性产下更多的卵。手术性别比（不分年龄）对后代的总发育持续时间没有显着影响。在不同年龄组中，所有性别比例治疗中，年长的男性花更多时间开始交配，并且交配时间更长。当雌性与年长的雄性交配后代发育时间延长时，第一窝卵的数量最低。因此，可以得出结论，男性偏向的性别比可提高性巨嘴鸟的性能。。在不同年龄组中，老年男性的表现较青年和中年男性差。