RELATIONSHIP BETWEEN PUPAL COLOUR AND SEX RATIO OF THE COMMON MORMON, Papilio polytes romulus CRAMER, 1775 (INSECTA: LEPIDOPTERA), SRI LANKA

A free ranging female common Mormon (Papilio polytes romulus) butterfly was observed laying eggs on a Citrus aurantiifolia (Family: Rutaceae) plant in a home garden in Battaramulla. 16 eggs were collected and reared in the lab. The duration and measurements of each stage were recorded. After eclosion the sex and wingspan of all adult butterflies were recorded and they were released back to the wild. Pupae were observed in two colours: green and brown. Out of 16 pupae, 12 were green (75%) and four were brown (25%). The four brown pupae gave rise to two males (50%) and two females (50%). The 12 green pupae gave rise to 10 males (83%) and two females (17%). The sex ratios regardless of the pupal colour showed male dominance with 12 males (75%) and four females (25%). All four females were of the romulus form. A strong relationship between pupal colour and substrate texture was observed, but no relationship between pupal colour, sex and sex ratios was seen.