The study examined key biological and ecological traits of Cyamophila willieti, a major pest of Styphnolobium japonicum, including its circadian mating rhythm, oviposition preference, and temperature-dependent population performance. Using the age-stage, two-sex life table approach, we compared the development, reproduction, and population growth potential of C. willieti under three temperature regimes. Results showed that mating activity followed a bimodal circadian rhythm with peaks at 12:00 and 17:00, while females showed a strong preference for ovipositing on shoot tips. C. willieti achieved higher population growth rates at 25 °C compared to 29 °C and 33 °C, with an intrinsic rate of increase (r) of 0.1885 ± 0.0086 day-1, a finite rate of increase (λ) of 1.2075 ± 0.0104 day-1, a net reproductive rate (R0) of 215.92 ± 43.00 offspring per individual, a mean longevity of 35.03 ± 2.02 days, and a fecundity of 647.75 ± 52.94 eggs per female. Compared with 29 °C, r, R0, and fecundity were 2.95-, 34.0-, and 13.6-fold higher at 25 °C, respectively, whereas most nymphs failed to develop beyond the fifth instar at 33 °C. Our results suggest that 25 °C was more favourable for the development, reproduction, and population growth of C. willieti than the higher temperatures of 29 °C and 33 °C, providing a basis for its monitoring and sustainable management.
