The present investigation elucidates the morphometric and chronobiological dynamics of the developmental stages of Eudocima materna (Lepidoptera: Erebidae) under controlled laboratory conditions. The study integrates quantitative morphometric measurements and time-based developmental observations across egg, larval, pupal, and adult stages. The total life cycle was completed within 32.40 ± 0.79 days. Progressive allometric growth, distinct instar-specific differentiation, and a synchronised developmental rhythm were observed. The larval phase, encompassing five instars, exhibited exponential increases in mass, length, and head capsule width. Pupation marked a phase of histogenesis and structural reorganization, while the adult stage displayed notable sexual dimorphism in morphology and lifespan. The findings contribute to a refined understanding of the species’ life-history strategy, supporting ecological modeling and pest management frameworks involving E. materna.