Submitted to: The Canadian Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 1, 2001
Publication Date: April 1, 2001
Citation: Horton, D.R., Lewis, T.M., Hinojosa, T.L. 2001. Copulation duration and probability of insemination in Anthocoris whitei Reuter (Heteroptera: Anthocoridae) as a function of male body size. The Canadian Entomologist. 133:109-117. Interpretive Summary: Reproductive success in insects depends upon a number of factors, including whether a given male is successful at transferring sperm to the female. In many species, male body size may affect success at mating and egg fertilization. In the present study, we determined how male size in a predatory true bug, Anthocoris whitei, affects success of the male in fertilizing the female, and monitored how this relationship is affected by artificially shortened matings and matings done at less than optimal temperatures. Larger males were more successful than smaller males at transferring sperm to the female, particularly at extremely shortened matings and for matings conducted at cool temperatures. These results assist our understanding of the reproductive biology of this important natural enemy, and could contribute in the future if this species is reared in the laboratory for release in the field.
Technical Abstract: Copulation duration in Anthocoris whitei Reuter decreased significantly with increasing male length or width, albeit with high levels of unexplained variation. Duration also decreased with increasing temperature, averaging 104 minutes at 25 deg C and 178 minutes at 15 deg C after adjustment of the data for male size. Female length and width had no effects on copulation duration. We interrupted copulation at 20 minutes or 40 minutes at both 25 deg C and 15 deg C to determine the interacting effects of male size, temperature, and copulation duration on probability of insemination. Insemination probabilities increased with increasing male size, increasing temperature, and increased duration of copulation. Large males were more successful than small males at inseminating females at cool temperatures and for severely shortened copulations.