Eurycorypha conclusa, Hemp, 2013

Heller, Klaus-Gerhard & Hemp, Claudia, 2020, Hyperdiverse songs, duetting, and the roles of intra- and intersexual selection in the acoustic communication of the genus Eurycorypha (Orthoptera: Tettigonioidea, Phaneropterinae), Organisms Diversity & Evolution (New York, N. Y.) 20 (4), pp. 597-617 : 601-602

Eurycorypha conclusa ( Figs. 3 , 4a , 6 , and 7)

The calling song of E. conclusa differs from all other known Eurycoryphya songs because it contains long (1–9 s), homogenous series of syllables ( Fig. 4a ). These long echemes occurred typically in mixed series interspersed with short echemes ( Fig. 7a ). The series were separated by long intervals (several to many minutes). During these times, the males produced short echemes lasting 50–400 ms. Occasionally, a male may also sing several hours without producing long echemes. The short elements were (often much) louder and much more common than the long ones and relatively variable in their intervals (e.g., 0.5–60 s, sometimes in pairs or groups), amplitude and in number (3–13) and composition (one to a few impulses) of syllables. The syllables typically contained more impulses in the long than in the short echemes. Before a long echeme is registered, often the short elements became longer and the intervals shorter so that a more or less continuous transition could be observed. In both types of echemes, the syllables were repeated at a rate of 30–50 Hz ( T = 20–26 °C) .

The females responded to the male song typically about 200 ms after the beginning of a short echeme ( Figs. 5 and 7 c ; means of four females: 292 ± 71 ms, n = 46, T = 20 °C; 149 ± 20 ms, n = 11, 154 ± 31 ms, n = 10; T = 23 °C; 164 ± 16 ms; n = 10; T = 25.5 °C). If the male echeme was longer than the female latency, the female response occurred before its end ( Fig. 7e, f ). The female responses were often also placed between the two short echemes of one echeme pair ( Fig. 7b, d ). However, all four females answered occasionally also directly after the end of a long echeme ( Figs. 5 and 7b ; delay after the last syllable, means, 205 ± 34 ms, n = 9, T = 20 °C; 201 ± 41 ms, n = 9, 169 ± 21 ms, n = 4; T = 23 °C; 204 ± 33 ms, n = 10, T = 25.5 °C). In this situation, one young female, just beginning to respond, produced a few responses with unusual large delays of 1–2 s (n = 6). The female responses consisted of one to several loud impulses, often accompanied by some soft sounds .

Figures

Fig. 3 Power spectra of male calling song of Eurycorypha species. In species with restricted frequency range, short black lines mark its end. Blue lines indicate power spectra of female responses

Fig. 4 a, b Oscillograms of male calling songs, overview (10 s sections)

Fig. 6 Oscillograms of male- female duets, overview (10 s sections)

Fig. 7 Eurycorypha conclusa. a Overview of a series of long echemes in male song (40 s section). b, f Male-female duets, details

Fig. 5 Oscillograms of male calling songs, details (1.5 s sections)