REPRODUCTIVE BEHAVIOUR OF TWO APHIDOPHAGOUS LADYBEETLES, CHEILOMENES SEXMACULATA AND COCCINELLA TRANSVERSALIS

Abstract  Reproductive behaviour of two aphidophagous ladybeetles, Cheilomenes sexmaculata and Coccinella transversalis was studied. A premating period of 5.0±0.5 and 11.7±0.4 days and a pre-oviposition period of 5.5±0.7 and 12.7±0.5 days was observed for C. sexmaculata and C. transversalis , respectively. Males of both the species exhibited courtship in five steps, viz . approach, watch, examine, mount and attempt. Sexually immature, recently mated and ovipositing females rejected male advances in both the species. Chemical, visual and behavioural cues probably play a role in mate recognition. Quiescent mating occurred in C. sexmaculata , whereas abdominal shakings in the form of bouts and strokes were characteristic in C. transversalis. C. sexmaculata had a relatively prolonged mating duration (133.4±z8.9 min) than C. transversalis (37.9±2.0 min), possibly due to the absence of active processes, i.e ., bouts and strokes. The active processes in C. transversalis decreased with multiple matings in a day. Unmated adults of both the species mated more vigorously than the mated ones. Reproductive performance of both the species was best after multiple matings.