Physalaemus soaresi Izecksohn, 1965

Hepp, Fábio & Pombal, José P., 2020, Review of bioacoustical traits in the genus Physalaemus Fitzinger, 1826 (Anura: Leptodactylidae: Leiuperinae), Zootaxa 4725 (1), pp. 1-106 : 70

Physalaemus soaresi Izecksohn, 1965

We found a single call type for the species, referred to as call A. The call is composed of a single harmonic note with long duration, PFM, and a slight PAM, with no silence intervals. Bands have a general upward FM and a downward FM at the end, yielding arc-shaped bands in audiospectrogram when considering the entire call. Subharmonics, shifts of the fundamental frequency and deterministic chaos are common at the beginning and end of the calls.

Call A ( Fig. 38 A–J and 33F). We examined three recordings, a total of five minutes, with 40 calls from five males. Only some of these calls were measured (see Table 2 ). Call duration varies from 1.597 to 1.748 s. In most calls, the limits between the call rise, sustain, and fall are not clear. Usually, call rise and fall are similar in duration and shape (logarithmic). In some calls, the rise is longer than fall. There is a long sustain. It is usually regular, with a convex shape, but it can be almost flat ( Fig. 38A, C ), or have irregular AM segments, yielding amplitude peaks and valleys over the segment ( Fig. 38D, E, F ). The amplitude peak is usually at around the middle of the call duration. The envelope of the call varies between elliptic ( Fig. 38A, C ), rectangular (Fig. E, F), or triangular (pointed left; Fig. 38D ), depending on the shape and steepness of the sustain. More than 50 % of the call energy is concentrated in 39 % of the call duration around the amplitude peak. Some calls have a slight PAM (there is no silence interval between peaks; Fig. 38F ). The rate of the PAM is ca. 16 Hz, forming ca. 22 amplitude peaks throughout the call. The call has a harmonic series ( Fig. 33F ). The fundamental frequency is ca. 600 Hz. This band and the next harmonic are absent in the audiospectrogram. There are usually ca. six emphasized harmonics. Generally, the wave periods are regular and harmonics are clear throughout the call. However, subharmonics (f 0 1/2), jumps of the fundamental frequency, and deterministic chaos are common at the beginning and end of the call ( Fig. 38B, G, H, I, J ). The dominant frequency varies from ca. 2450 to 3060 Hz. The dominant harmonic varies from the second to the seventh, but it is usually the fourth or fifth ( Fig. 33F ). There is no clear shift in the relative energy between the bands throughout the call ( Fig. 33F ). Most of the call energy is between 2250 and 3750 Hz (three harmonics). The call has a general upward FM and a short downward FM at the end, yielding an arc-shaped bands in audiospectrogram when considering the entire call ( Fig. 38B, G, H, I, J ). Additionally, there is clear PFM throughout the call, which is usually independent from the PAM or can be directly proportional and synchronic to some parts of the PAM ( Fig. 38 A–J).

Figures

FIGURE 33. Multiplicity relationship between “instantaneous” dominant frequency and w of calls A of eight Physalaemus species. Each graph shows a single call A of P. cuvieri (A), P. ephippifer (B), P. fischeri (C), P. cicada (D), P. aguirrei (E), P. soaresi (F), P. maximus (G), P. feioi (H). Grid corresponds to the harmonic values (right y-axis). Red squares are the values of “instantaneous” dominant frequency; blue circles are the values of the reciprocal of w; green triangles are the factor values of the ratio “instantaneous” dominant frequency / w reciprocal per delta time. Delta time corresponds to the duration of one period of the measured acoustic oscillation. Note that factors around integer values suggest harmonic relationship between the frequency calculated (w reciprocal) and the dominant frequency. Factors multiple of ½ of the fundamental frequency correspond to subharmonics (see P. ephippifer; B).

FIGURE 38. Call A of Physalaemus soaresi. Oscillograms (A, C–F) and audiospectrograms (B, G–J). A typical call (A–B). Variant calls with different envelopes and spectral features (C–J). Note the frequency jumps, deterministic chaos, and subharmoncis at the beginning and or end of the calls (B, G–J). Horizontal scale bars have 0.5 s; vertical scale bars have 1 kHz. Filter bandwidth (Hz): 55.2 (B and H); 39.5 (G); 42.3 (I); 50.7 (J).