Physalaemus marmoratus (Reinhardt & Lütken, 1862)

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 : 78

Physalaemus marmoratus (Reinhardt & Lütken, 1862)

We found a single call type for the species, referred to as call A. The call is composed of a single harmonic note. It has a general downward FM, with an up-downward FM segment in the first third of the call.

Call A ( Fig. 47 A–J and 42F). We examined 15 recordings, a total of 31 minutes, with ca. 1100 calls from 44 males. Only some of these calls were measured (see Table 2 ). Call duration varies from 0.614 to 0.938 s. The envelope of the call is highly variable ( Fig. 47A , C–F). In most calls, the limits between the call rise, sustain, and call fall are not clear. The ratio between durations of call rise and fall, and their shapes, are highly variable. The sustain is usually irregular, composed of shallow valleys and small peaks ( Fig. 47A , C–F). In some calls the rise remains with very low amplitude until the limit with the sustain, where the amplitude increases abruptly ( Fig. 47D ). In other calls, the call fall has this same pattern, with an abruptly amplitude decrease after the sustain and thenceforth with low and constant amplitude until the end of the call ( Fig. 47C ). The amplitude peak is usually at around the end of the first third of the call duration. The envelope of the calls varies from rectangular ( Fig. 47E, F ) to triangular (pointed left or right; Fig. 47D, A , respectively). Due to the asymmetry of some triangular envelopes, the shape resembles an arrow. More than 50 % of the call energy is concentrated in 29 % of the call duration around the amplitude peak. There is no PAM in the call. The call has a harmonic series ( Fig. 42F ). The fundamental frequency is ca. 510 Hz and the first six harmonics are generally emphasized. The wave periods are regular and harmonics are clear throughout the call. The dominant frequency is ca. 500 Hz ( Fig. 47B ). The first is dominant harmonic ( Fig. 42F ). There is a clear shift in relative energy between bands; although there is no shift in dominant frequency, the higher bands get more energy toward the end of the call ( Fig. 47 G–J). Most of the call energy is between 400 and 2100 Hz (three to five harmonics). The call has a general downward FM ( Fig. 47B , G–J). Additionally, the calls have an up-downward FM in the first third of the call duration, leading to slightly arc-shaped bands in this part of the call, and short downward FM at the end ( Fig. 47B , G–J). The general downward FM and the initial up-downward FM result in S-shaped harmonics when considering the entire call. There is no PFM.

Figures

FIGURE 42. Multiplicity relationship between “instantaneous” dominant frequency and w of calls A of eight Physalaemus species. Each graph shows a single call A of P. orophilus (A), P. lateristriga (B), P. olfersii (C), P. riograndensis (D), P. biligonigerus (E), P. marmoratus (F), P. santafecinus (G), P. carrizorum (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 call B of P. ephippifer).

FIGURE 47. Call A of Physalaemus marmoratus. 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 different slopes in the FM segments (G–J). Horizontal scale bars have 0.1 s; vertical scale bars have 1 kHz. Filter bandwidth (Hz): 67.4 (G); 55.2 (H); 67.4 (I); 46 (B and J).