Acoustic and Associated Behavior of the Coneheaded Katydid, Neoconocephalus nebrascensis (Orthoptera: Tettigoniidae)

Abstract

Males of the coneheaded katydid, Neoconocephalus nebrascensis (Bruner), produce calling, male/male contact (aggressive), precopulatory, and disturbance sounds. Males may produce solo calling sounds but usually their calling sounds are synchronous with those of nearby males. During paired synchrony, the leader male produces a longer phrase and begins his phrase before and ends his phrase after the follower. As interkatydid distance is shortened, followers shorten their phrases. Males continue to synchronize when close, even when touching. Eventually the follower ceases calling and moves away. If males are not singing, antennal contact of another male may elicit the contact song from either male. Contact songs consist of shorter phrases and longer phrase intervals than solo or synchronized calling. Short bursts of male calling during the day, the first phrases of solo calling, and the precopulatory song are similar to contact songs except that the latter include short, clicklike sounds following some phrases. Such clicks are characteristic of male/male interactions in other katydid species. The disturbance sound is a single click produced during closing of a male's wings in response to tapping on a male's cage, movement of a male's perch, and before flight or hopping. Precopulatory songs are only elicited following antennation of a virgin female, contain no clicks, are produced by previously calling or silent males, and appear softer than other sounds. As in most strictly nocturnal singing orthopterans, physical fighting is rare. Fighting consists of raking with front legs, abdominal raking (performed in the parallel and opposite position characteristic of attempted copulations of females), and head butting, which may include biting without injury. Occasionally, males and females will tremulate (body shake) during male/male and male/female interactions.