Reproductive behaviour of a generalist aphidophagous ladybird beetle Cheilomenes sexmaculata (Coleoptera: Coccinellidae)

Abstract

The reproductive behaviour of a generalist aphidophagous ladybird beetle Cheilomenes sexmaculata (Fabricius) was studied in detail. The males first mated at an age of about 2 days, while females mated at 1 day after their emergence. Mate recognition was displayed in five steps, viz. approach, watch, examine, mount and copulatory attempt. Being provided with four dummy models, the male appeared to recognize the female through visual and other possible cues, maybe chemical. The duration of mating was maximum (mean ± SE; 133.0 ± 2.8 min) when an unmated male copulated with a virgin female and minimum (95.0 ± 4.2 min) when a mated male copulated with a mated female. Mating duration seems to be influenced more by the change in male sexual status, thus revealing it to be male dominated. The maximum oviposition period (46.0 ± 1.2 days), fecundity (861.0 ± 2.2) and hatching percentage (64.0 ± 0.6) in C. sexmaculata were noticed after multiple matings, while these parameters were minimum (15.0 ± 1.0, 70.0 ± 2.8 and 37.0 ± 1.0, respectively) after single mating. Thus, multiple matings enhanced the total egg output and percentage of hatchability.