Ectadia diuturna Heller & Liu, 2017

Song.— Time-amplitude-pattern. In Ectadia diuturna sp. n. one song unit typically lasted about 30 to 60 s (all data for 25°C ex- cept otherwise mentioned; up to 80 s in the  eld at 18°C). It was followed by the next unit after a silent interval as short as some seconds, but also as long as some minutes. The shortest intervals were observed when males and females were in acoustical con- tact. Each unit contained four phrases each of which consisted of a different combination of micro- and macrosyllables. A simple and clear example is shown in Fig. 10A. However, often the differ- ent phrases were connected by transitional phrases. A song unit started with a series of tick-like microsyllables, separated by inter- vals of about 150 ms (phrase A; see Fig. 11 for details). Sometimes the intervals between the ticks were larger and more irregular. Be- tween these loud syllables (occasionally?) short and soft sounds were observed. At the end of a phrase typically two tick sounds fol- lowed each other quite closely (10 ms interval) a few times. Such phrases were also heard isolated outside complete song units, possibly representing unsuccessful attempts to start a song unit. After this phrase a series of macrosyllables followed (phrase B), in which always two types of impulse groups alternated, a long series (ca. 70 impulses; duration 120 ms), sometimes split into two or more by one or several unusually large intervals, and a short series (ca. 55 densely packed impulses; duration 30-40 ms). Both groups differed distinctly in carrier frequency (see below). In amplitude, this phrase was always lower than the loud phrase A. Its duration was the most variable of all phrases, from nearly missing up to ten seconds. Phrase C consisted of a long series of stereotypic ele- ments (period about 500 ms), each containing two pairs of im- pulse groups as seen in phrase B. These pairs were separated from the next pair by an interval of about 200 ms. During this interval one (or two) loud microsyllables were produced and addition- ally a series of softer isolated impulses. While in Fig. 10 an abrupt change from phrase B to C can be seen, in many other recordings there is a long transition with phrase C elements appearing more and more frequently (see e.g. Fig. 12). Phrase D  nally consisted of several repetitions of the impulse series from phrase C (period about 400 ms) without macrosyllables.

The females responded near the end of a song unit (Fig. 12). They answered mostly not only once, but several to many times (1–25 responses per song unit). The responses occurred nearly al- ways during phrase D, and often also additionally at the end of phrase C. Very rarely they were heard during phrase A, in this case the females possibly assuming a late phrase D from the previous song unit. In many phaneropterine species, the females respond with a species-speci c delay after the male song or some parts of it (e.g. Heller and Helversen 1986). This is probably also the case in E. diuturna sp. n., but the response delay is dif cult to measure exactly, because often several possible trigger events are closely to- gether, and the response consists of several loud impulses distrib- uted over more than 100 ms. The delay is obvious in the range of 150–250 ms. In any case, often very soft impulses (more than 20 dB softer than the main response) were observed that occurred much faster (70–80 ms) than the loud impulses.

Carrier frequency.— During one song unit, parts with quite different spectral composition were observed. The short, tick-like elements of which phase A and D consisted and which occurred also in phase C, had always a quite similar spectrum. Its peak was situated at about 20 kHz, in the lower half with strong components starting abruptly at about 5 kHz, in the higher half continuously decreas- ing in power until 40 kHz (Fig. 13). Also the softer and shorter impulse groups found in phase B and C were similar to this pattern presenting a relatively narrow peak at 20 kHz and a side-peak at 40 kHz. However, the longer and often louder impulse groups from phase B and C differed distinctly. Their spectrum contained two clearly separated peaks. Besides a high and narrow peak at 10 kHz it showed a broad maximum at 60 kHz (Fig. 13). These impulse groups alternated with the shorter and softer impulse groups (see  g. 5 in Heller et al. 2015). The female response had its maximum between 10 and 20 kHz (recorded in audible range only). [1]

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