MIRANHA IMBELLIS (FIG. 5)

Seasonal rhythm. Began at the end of the dry season and probably continued during a part of the wet season, but the exact time of the decrease in activity is unknown.

Nycthemeral rhythm. Main activity at dawn and dusk with irregular activity during the day.

Calling site and calling posture. Called on trunks. Vertical movements of the abdomen coincided with the amplitude modulations.

Calling song. Began with a succession of 2–7 echemes of 5.44 s ± 0.94 (4.19–7.33, 9) (part A) and ended with a long buzzing song of 5.76 s ± 2.42 (1.96–10.80, 12) (part B). Parts A and B might alternate several times without silent intervals. The energy of the spectrum was mainly concentrated on one frequency band at about 4300Hz. Part B was composed of a train of two pulse-groups. Pulses were repeated with a rate of 153 Hz.

Behaviour. Formed groups of 2–4 individuals spaced on close trees, sang in chorus with synchronization of part B of the song.