Bioacoustics of Pseudophlepsius binotatus

Description. Pale yellowish with whitish forewings. Head, pro-, and mesonotum with numerous small dark spots; head also with two larger black spots on fore margin next to midline. Forewings with brown veins and with dense fine line or speckled pattern ( Figs. 8–17 ). Intensity of dark pigmentation varies greatly even between specimens from same sample ( Figs. 9–10, 11–12 ). Aedeagus U-shaped, stems wide, with denticles in distal halves on ventral side ( Figs. 56–67 ). Stem apices broadly or narrowly rounded (for example, Figs. 59, 62–63 ), sometimes wide angular and obliquely cut ( Figs. 58, 64, 66–67 ); specimens with different penis shape can be found in the same sample ( Figs. 56–59 ). Basal processes narrower than in Eremophlepsius , curved inwards, with hook-like tips. Position of processes in relation to penis stems varies, which is visible in lateral view ( Figs. 57a–62a, 64a–67a ). Styles with long narrow tips evenly bent outward ( Fig. 68 ). Valve large, subgenital plates without macrosetae, with elongated narrow tips. Pygofer lobes with rather narrow, rounded apices and pointed, almost straight, directed slightly dorsally ventral processes ( Figs. 69–70 ). Body length: ♁, 4.6–5.4 mm ; ♀ , 5.7–6.4 mm . Male calling signal. Signals of males from four localities were investigated ( Fig. 40 ). 1. Southern Turkmenistan , Dushak village , ca. 170 km SE of Ashkhabad , from Alhagi persarum in the desert, 19. V. 1990 , signals of two males recorded at 26 oC . 2. Southeastern Kazakhstan , environs of Aksu village , 20 km N of Zhasagurov , from A. pseudalhagi near the river, 27. VI. 2019 , signals of two males recorded at 29–31 oC . 3. Southeastern Kazakhstan , Urzharsky Region , 27 km south of Taskesken , A. pseudalhagi in the steppe on the riverbank, 24. VI. 2022 , signals of three males recorded at 35–37 oC . 4. Russia , Lower Volga Region , Dosang Railway Station , ca. 60 km N of Astrakhan , from A. pseudalhagi in the desert, 2. VII. 2000 , signals of three males recorded at 26 oC . Calling signal is a phrase lasting from 1–1.5 up to 4 s in our recordings ( Figs. 45–48 ); phrase duration can vary between the males from the same locality ( Figs. 45–46 ). Phrase begins with a variable train of pulses with lower amplitude and ends with a high-amplitude syllable usually consisting of four pulses ( Figs. 49–55 ). Sometimes, one or several high-amplitude syllables also present in the middle part of a phrase ( Figs. 51–53, 55 ). The ratio of the amplitudes of the initial part of the phrase and the final syllable also varies in males from the same locality ( Figs. 54–55 ). As in other insects, pulse repetition period decreases with increasing temperature (cf. Figs. 51 and 52 ).