Bioacoustics of Philipsalta exilis

Song ( Figure 18 ) About 190 s of song was recorded from this species at the type locality, including that of the paratype male, which is illustrated here. Males produce song phrases of about 0.3– 0.85 s duration at a regular pace of about 0.5 phrases/s. Each phrase begins with about 8–20 doublet pulses produced at 40 doublets/s, with the first pulse of each doublet louder. The doublets increase in intensity towards the end of this long syllable. After a gap equivalent to the time needed for one additional doublet, the phrase concludes with a syllable of 6– 13 doublets produced at a faster rate (60/s) and with a greater intensity. In our recording, it is difficult to discern the quieter pulse of each doublet in the second syllable. There is a tendency, across phrases, for pulse doublets to drop out occasionally within both syllables. The recording was taken with the recordist close to the cicada and attempting to attract it with finger-snaps, so disturbance could have occurred. The frequency spectrum is broad, reaching from at least 8 kHz to above 20 kHz, but most energy is concentrated within the range 8–12 kHz. The dominant frequency is about 10 kHz. Males sang from perches on vertical surfaces (e.g. ferns, tree trunks, small branches) around 2–4 m aboveground in the forest interior. The song of Philipsalta exilis Lee and Marshall sp. nov. can be distinguished from that of the next new species of Philipsalta (below) by the absence of a short single-doublet element ending many of the phrases and by the uniform rate of production of pulse doublets within the first syllable/echeme. Philipsalta exilis and P. nigrina have a similar song structure, but in the latter species the pulses in the first section of each phrase form widely separated four-pulse syllables, the intervening gaps being much longer than the syllables.