Acoustic communication in the Malaysian giant long-legged katydid (Macrolyristes corporalis)

The Malaysian giant long-legged katydid (Macrolyristes corporalis) is a large forest-dwelling Orthopteran insect in the family Tettigoniidae. Males produce an intense sexual signal to attract females, with most calling restricted to nocturnal bouts. Here we describe for the first time the acoustic structure of the male sexual signal from recordings taken in 2011 from a population maintained for educational purposes by the St. Louis Zoo. We address the following questions: 1) what are the spectral characteristics of the male calling song? 2) what are the temporal characteristics of the male calling song? and 3) what are the morphometrics of the male sound producing structures? Males produced long trains (103.33±151.64 s) of continuous trills with a pulse rate of 135.54±27.18 pulses/second and with a dominant frequency of 2.7±0.11 kHz. The average length of the plectrum was 12.32±0.85 mm, while the width averaged 1.46±0.43 mm. The average stridens length was 15.21±0.86 mm, with an average width of 1.94± 0.17 mm. The stridens consisted of a curvilinear structure with individual ridges averaging 48±5.18 ridges per structure. Future work will test hypotheses regarding the encoding of male size in the calling song, female preference, and insect audition through playback, choice, and electrophysiology experiments.