Physalaemus jordanensis Bokermann, 1967

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 : 86

Physalaemus jordanensis Bokermann, 1967

We found a single call type for the species, referred to as call A. The call is composed of a single harmonic note with an elliptic or triangular envelope. The call is composed of a sequence of pulses (pulse-PAM) with silence intervals between pulses. It has a general downward FM throughout the call but with a short and slight up-downward FM segment in the first seventh of the call duration.

Call A ( Fig. 55 A–N and 52E). We examined 20 recordings, a total of 47 minutes, with ca. 1100 calls from 55 males. Only some of these calls were measured (see Table 2 ). Call duration varies from 0.980 to 1.961 s. The envelope of the call is variable. The call rise and fall are very short and similar to each other. The sustain is irregular ( Fig. 55G ), generally flat ( Fig. 55A, C, F ) or ascending ( Fig. 55E, H ). There is usually a long shallow valley at the beginning or at the middle of the sustain. In several calls, the first half of the envelope has lower amplitude than the second half. The amplitude peak is usually at around the end of the first four fifths of the call duration. The envelope of the calls varies from elliptic ( Fig. 54A ) to rectangular ( Fig. 55C, F ) or triangular (pointed left; Fig. 54E, G, H ). More than 50 % of the call energy is concentrated in 45 % of the call duration around the amplitude peak. The call has a strong PAM (silence intervals are present between pulses; Fig. 55 A–N). The rate of the PAM is ca. 20 Hz, forming ca. 31 pulses throughout the call. The interpulse intervals are variable but they are usually fourfold longer than the pulse duration. Silence intervals are absent between the last pulses of the call (pulses are juxtaposed; Fig.55D, J )). The last pulse longer than the others ( Fig. 55A, B, C, D, E, I, J, K ). The call has a harmonic series ( Fig. 52E ). The fundamental frequency is ca. 450 Hz and approximately the first seven harmonics are emphasized. The wave periods are regular and harmonics are clear throughout the call. The dominant frequency varies from ca. 560 to 2440 Hz ( Fig. 55B ). The dominant harmonic varies from the first to the sixth (except the third), but during the first half of the call, it is usually the first ( Fig. 52E ; 55B , I–N). There is a clear shift in relative energy among the bands; the dominant frequency increases towards the end of the call, starting at the first harmonic, moving to the fifth and ending at the sixth; at the end of the call, the dominant frequency jumps among the first, fourth, fifth and sixth harmonics ( Fig. 52E ; 55B , I–N). Most of the call energy is between 400 and 3700 Hz (five to six harmonics). The call has a general downward FM, a short and slight up-downward FM in the first seventh of the call duration, leading to slightly arc-shaped bands in this part of the call, and usually a short upward FM at the end ( Fig. 55B , I–N). The general downward FM and the initial up-downward FM result in S-shaped harmonics when considering the entire call. Additionally, there is PFM throughout the call, which is directly proportional and synchronic with the pulse- PAM ( Fig. 55D, J, G, M ).

Figures

FIGURE 52. Multiplicity relationship between “instantaneous” dominant frequency and w of calls A of four Physalaemus species. Each graph shows a single call A of P. gracilis (A), P. lisei (B), P. evangelistai (C), P. barrioi (D), P. jordanensis (E). 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.

FIGURE 54. Call A of Physalaemus barrioi. Oscillograms (A, C–G) and audiospectrograms (B, H–L). A typical call (A–B). Variant calls with different envelopes (C–L). Note the subharmonics at the middle of the call (B). Horizontal scale bars have 0.5 s; vertical scale bars have 1 kHz. FFT (points): 2000 (H, J, and I); 2500 (B); 1024 (K); 1500 (L).

FIGURE 55. Call A of Physalaemus jordanensis. Oscillograms (A, C–H) and audiospectrograms (B, I–N).A typical call (A–B). Variant calls with different envelopes (C and I; E–H, K–N). Final pulses of a call (D and J). Note the longer duration of the final pulse (D and J). Horizontal scale bars have 0.3 s (C and I; E–H, K–N) and 0.1 s (D and J); vertical scale bars have 1 kHz. Filter bandwidth (Hz): 135 (L); 78.9 (M); 110 (J); 61.4 (N); 69 (I and K); 61.9 (B).