Montana tomini Pylnov 1916

Montana tomini (Pylnov, 1916) — Figs. 7 J1, 7J2.

Localities: Russia, S Siberia, Tuva, 3.5 km to N of village Ersin (N 50°15', E 95°09'), 12.ix.1986, leg. O. Korsunovskaya (2 males). Mongolia, Selenge Aimag, Khonin Nuga, meadows, (N 49°05', E 107°18'), 900–1000 m a.s.l., 20–21.viii.1997, leg. K.- G. Heller (1 male). Mongolia, Selenge Aimag, Tal ca. 20 km east northeast (D) Züünkharaa (N 48°54', E 106°42'), 1050 m a.s.l., 19.viii.1997, leg. K.- G. Heller (1 male). Mongolia, Töv Aimag, forested hills, ca. 20 km north of Tereldsch (N 47°48', E 107°42'), 1850 m a.s.l., 15.viii.1997, CH 5317, leg. K.- G. Heller (1 male; Fig. 7 J2).

The most characteristic property of the calling song of M. tomini is the extraordinarily large duration of its syllables (Fig. 7 J). At 20°C the last syllable of a bi-syllabic echeme lasted about 200 ms. Only M. helleri is in the same range (150 ms at 30°C). However, both species differ considerably in the number of impulses per syllable: M. helleri has 32 impulses (and 39 teeth in the stridulatory file; Ciplak et al 2006), M. tomini ca. 80 impulses (and 108 teeth; Fig. 6 C). Concerning the number of syllables per echeme, there is a surprising variability (Figs 7 J1, 7J2). One animal (CH 5317) showed consistently always three to six (eight) syllables per echeme (cage recording at 16°C), the others only two to four.