Bioacoustics of Calipsalta brunnea

Measurements . Range and mean (in mm) for 10 males , 10 females (includes smallest and largest of available specimens). Length of body (including head): male 18.9–24.6 (21.4); female (including ovipositor) 19.6–25.6 (22.8). Length of forewing : male 20.9–27.6 (23.9); female 21.9–27.4 (24.7). Width of head (including eyes): male 5.8–7.6 (6.6); female 6.1–7.6 (6.7). Width of pronotum (across lateral angles): male 7.1–9.0 (7.8); female 7.1–9.4 (7.9). Distinguishing features . Light brown cicadas in life. The forewing is lightly infuscated subapically, the venation is brown, and the rostrum reaches about mid length of mid coxae. Forewing veins M and CuA are either fused at the basal cell for a short distance or unfused but abutted together. The male genitalia have pseudoparameres that are longer than the length of the thecal shaft and a ventral support that is about half the length of the pseudoparameres. The female ovipositor sheath barely protrudes beyond the anal styles and caudal beak. Calipsalta brunnea sp. n. is most likely to be confused with discoloured individuals of C. fumosa sp. n. that have turned brown after death; the mid brown to black forewing costa of C. brunnea distinguishes it from the pale brown or pale greenish costa of C. fumosa . Song ( Figs 50a–d ). Recordings were examined from the type locality and the following paratype localities: NT.HME, NT.PCK, WA.DEE, WA.NSR. The calling song consists of a train of sharp clicks or doublets that oscillates between slower and faster click rates at about 14–23 cycles/s and ends, after a brief silent gap of 0.045 –0.065 s, with an isolated syllable lasting about 0.02 s (sometimes containing only a single click). Click rates vary from 140–31/s. This oscillation is so rapid that normally only one slow-rate click is produced per cycle, and only two or three fast-rate clicks. Phrases may last longer than a minute. Most sound energy is found within the range 8–14 kHz, with a peak around 10 kHz. There is no frequency modulation. The song has been previously recorded from Cravens Peak Reserve in Queensland by Ewart (2009 , p. 143–144, “ Cicadetta sp. A ”), who described the song structure as repeated 4-syllable macrosyllables. The song of Calipsalta brunnea is similar to those of C. viridans sp. n. , C. fumosa sp. n. , and Pedana hesperia sp. n. , but is clearly distinguishable by its more rapid rate of oscillation between fast- and slow-rate sections, over 14 cycles/s compared to less than 7 cycles/s for the other species. Males call both during the day and at dusk. but tend to restrict calling to dusk when day temperatures are exceedingly high.