Female preferences for male song characters in the bush-cricket Isophya camptoxypha (Orthoptera, tettigonioidea)

Female preferences for two male song characters (duration of syllables [DS], syllable repetition period [SRP]) have been studied in Isophya camptoxypha, an Eastern European duetting bush-cricket. Songs with modified DS or SRP were presented to virgin females and their response songs were recorded and counted. Female preference functions were unimodal for both characters. But while in the case of SRP the obtained female preference function reached its maximum at the mean value of that character, in the case of DS females preferred modified songs with a DS slightly higher than the natural range of that character. A comparison between the obtained preference functions and the DS and SRP values measured in sympatric Isophya species (with similar song structure) suggests that the two examined characters and female preferences for them may be effective components of the species-specific mate recognition system of I. camptoxypha. Moreover DS values may also convey information about the quality of the singing male.