title: Do males bite females' antennae to coerce copulation or to continue mate guarding in Oiceoptoma subrufum (Coleoptera: Silphinae)?
abstract: In several species, males frequently immobilize females during copulation. In some species, female immobilization enables males to copulate with unwilling females, while in others, female immobilization prolongs postcopulatory guarding. Male carrion beetles often bite and pull hard on one of the female's antennae during copulatory mounting. Previous descriptive studies have hypothesized that antenna biting is important for postcopulatory guarding in Silphinae. Here, we observed the mating behavior of Oiceoptoma subrufum, to understand the roles of antenna-biting in the initiation and termination of copulation. We compared the success and duration of intromission and pre- and postcopulatory mounting duration between males that did and did not bite female antennae during copulatory mounting. The success and duration of intromission and precopulatory mounting duration were unaffected by antenna biting. However, antenna-biting males mounted females for longer after intromission compared to non-biting males. These results indicate that antenna biting contributes to postcopulatory guarding behavior, not coercive copulation, in O. subrufum.
authors.affiliation: Department of Biology, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata-shi 990-8560, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sumitomo
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Shiraishi
authors.forename: Tadao
authors.initials: T
authors.lastname: Hirota
mesh_terms: D000818:Animals; D001517:Coleoptera / Q000502:physiology*; D005260:Female; D008297:Male; D012726:Sexual Behavior, Animal / Q000502:physiology*
keywords: carrion beetles; mate competition; postcopulatory mate guarding; reproductive behavior; sexual conflict