Mating habits in the genus <i>Acraea,</i> with a possible explanation for monosexual populations (Lepidoptera: Nymphalidae: Acraeinae).

Abstract

Mating Acraea butterflies have been observed with rough "take-down" behavior by males and opposite dorso-ventral orientation of male and female abdomens, supporting theories of authors that males dominate copulation behavior without any pre-copulatory ritual, followed by use of a sphragis to protect their sperm investment in each female. The observations support the view that harassment of mated females may be a selective force which has led to genetic factors causing female-dominant populations in some Acraea species.