Bioacoustics of Isophya sonora

Measurements (Average, Standard Deviation, mm, n= 3 males ): Body length: 26.12 (0.51), Pronotum: 4.31 (0.29), Tegmina: 6.65 (0.09), Fore femur: 6.6 (0.41), Hind femur: 16. 30 (0.49). Calling Song . The songs were recorded in the evening, while the air temperature was 27°C. The calling song is very loud and consists of a series of irregular syllables repeated at the approximate rate of 0. 362 s ( Fig. 6A ). The syllables consist of 5–6 spaced crescendo impulses and nearly 34 densely formed decrescendo impulses ( Fig. 6 C–D). There are also some songs that produce 1–3 impulses right after the main syllables ( Fig. 6D ). The major part of each syllable lasts about 0.162 s . The carrier wave of the song has its intensive signals between 15–25 kHz, but the frequency components with detectable sound pressure spread over the frequency range of 5kHz–45kHz ( Fig. 7 ). Some other measurements of the male calling song are shown in Table 1 .

Description: Male. Fastigium verticis slightly narrower than scapus, distinctly narrowing distally, slightly depressed and sulcate dorsally ( Fig. 2A ). Lateral keels of pronotum distinct, almost parallel in prozona and very strongly diverging backwards on metazona up to caudal margin ( Fig. 2B ); frontal and caudal margin of the disk almost straight ( Fig. 2B ). Pronotum with concave margin in profile and distinctly elevated at metazona ( Fig. 2C ); paranota with frontal margin oblique, caudal margin long and oblique ( Fig. 2C ). Tegmina elongate, about more than 1.5 times the length of pronotum ( Fig 2D ); tegminal “disc” longer than wide, right margin of disc not projecting; speculum distinctly large, costal area of tegmen broadened ( Fig. 2B , 3 A–B, D). Stridulatory file about 2.82 mm , with about 66 teeth, each gradually widening and becoming progressively sparse towards the apex ( Fig. 4 , 5 A–D). The shape and width of the teeth in the distal and proximal part of the file are distinctly different from each other ( Fig. 5 C–F). The distance between tegmina edge and apex of the file is 0.60 mm . Fore femora 1.53 and hind femora 3.78 times as long as pronotum and without spines on ventral margins. Epiproct wide and long ( Fig. 3C ), extending to the middle of the cerci; cerci moderately long, proximal 3/4 narrowing distally; distal ¼–⅕ incurved into and wide angle, slightly narrowed subapically, with narrowly rounded apex and with a distinct denticle ( Fig. 2 D–E). Subgenital plate large at base, tapering posteriorly, with a deep rounded or “V” shape incision ( Fig. 2F ). Coloration as in Figures 3 A–D. Female: Unknown.