Objective This paper aims to clarify the morphological characteristics, developmental duration, annual life cycle, larval feeding capacity, and reproductive performance of adult female Serrodes campana at various life stages.

Method From 2022 to 2024, individuals were reared on fresh tender host leaves in a climate-controlled chamber. We recorded the morphological and developmental duration of each stage, measured larval leaf consumption and female fecundity, and observed the annual life cycle in a field net house in Jianning County, Fujian Province of eastern China.

Result (1) The main morphological characteristics of each life stage of S. campana are as follows: eggs are hemispherical with a reticulated pattern on the surface; larvae undergo six instars, with a greyish-black body adorned with orange stripes; the prepupae are greyish-white; pupae are reddish-brown, with a semi-circular tubercle-like protrusion on each side of reproductive pore of male pupa; adults have light brown hairs covering the body, two black spots at the base of forewings, the center panel differs in color from the front chest back panel and a kidney-shaped spot on the wing margin. (2) Stage durations (days, mean ± SE): egg (2.96 ± 0.00) d, larva (14.27 ± 0.04) d, prepupa (2.48 ± 0.04) d, pupa (11.71 ± 0.06) d, adult (12.29 ± 0.37) d; generation time (44.76 ± 0.47) d. Both laboratory and field observations showed that S. campana completed four generations per year in Fujian Province, with the earliest appearance of adults occurring in late April. (3) The larvae prefer feeding on plants of the Melia genus, with a significant increase in feeding from the 3rd instar onward, and the total feeding amount of a single larva reaching 53 601.75 mm². (4) The pre-oviposition period for females was (1.35 ± 1.00) d, the oviposition period lasted (8.20 ± 1.91) d, and the peak oviposition period lasted (6.45 ± 1.43) d. Mean fecundity was 921.70 eggs per female.

Conclusion Serrodes campana larvae pass through six instars, with the 5th to 6th instars being the main feeding and damaging stages, and female adults show relatively high fecundity, indicating a strong potential for population increase. In Jianning County, Fujian Province, this species completes four generations per year, with the second generation occurring in June to July as the population peak, while the adult stage of the first generation from May to June is the critical period for monitoring, early warning, and control intervention.