7. Streptanus aemulans (Kirschbaum, 1868)

Figs 29–31.

MATERIAL. Kyrgyzstan, Western Tien-Shan Mts., Chatkal Mtn. Range, Sary-Chelekskiy Nature Reserve, meadows on the northern shore of the Sary-Chelek Lake, 26.VII.2008, signals of one male recorded at 24–25 °C .

SIGNALS. The male calling signal is a phrase lasting for 15– 25 s (Figs 29–30). It consists of alternating syllables similar in the temporal pattern, but differing in the frequency spectra (Fig. 30). Syllables of both types include on average 6–8 pulses following each other with the repetition period of about 70–90 ms.

REMARKS. The structure of the male calling signals of S. aemulans is generally the same as in closely related S. sordidus (Zetterstedt, 1828) [Tishechkin, 2000: 47; figs 443–449], but differs in the pattern of syllables.

A remarkable feature of signals of S. aemulans is that syllables similar in the temporal pattern distinctly differ in frequency spectra.