How do "mute" cicadas produce their calling songs?

Area of Science:

• Bioacoustics
• Insect Communication
• Evolutionary Biology

Background:

• Cicadas primarily use tymbal mechanisms for sound production.
• The genus Karenia was previously considered "mute" due to lacking specialized sound organs.
• Understanding diverse sound production is crucial for insect communication research.

Purpose of the Study:

• To investigate the sound-producing mechanism in the
• To describe the characteristics of the impact sounds produced by K. caelatata.
• To determine the function of these sounds in K. caelatata's acoustic communication.

Main Methods:

• Morphological analysis of sound-producing structures.
• Reflectance-based analyses of relevant body parts.
• Acoustic playback experiments and behavioral observations.

Main Results:

• Discovered a new sound production mechanism: impact sounds generated by forewing costa striking the operculum.
• Identified modified morphological structures (forewing, operculum, cruciform elevation, wing-holding groove) involved in sound production.
• Confirmed impact sounds function as calling songs in intraspecific communication.

Conclusions:

• The discovery of impact sound production in Karenia caelatata expands the known diversity of cicada acoustic signaling.
• This finding highlights the need for further bioacoustic research on cicadas lacking tymbal mechanisms.
• Challenges the "mute" designation for Karenia, revealing sophisticated acoustic communication.