Physalaemus santafecinus Barrio, 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 : 79

Physalaemus santafecinus Barrio, 1965

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. 48 A–D and 42G). We examined two recordings, a total of three minutes, with 61 calls from two males. Only some of these calls were measured (see Table 2 ). Call duration varies from 0.330 to 0.375 s. The envelope of the call is variable. In most calls, the rise and fall are similar in duration and shape (exponential). In some calls, the limits between call rise, sustain, and call fall are not clear, with linear or logarithmic-shaped rise and fall and the sustain with a convex shape (calls with elliptic envelope; Fig. 48C ). The amplitude peak is usually at around the end of the first seven tenths of the call duration or at the middle of the call. The envelope varies from elliptic ( Fig. 48C ) to triangular (pointed left; Fig. 48A ). Due to the concave shape of the sustain, the triangular envelope of some calls resembles an arrow ( Fig. 48A ). More than 50 % of the call energy is concentrated in 36 % of the call duration around the amplitude peak. There is no PAM in the call. The call has a harmonic series ( Fig. 42G ). The fundamental frequency is ca. 490 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. 474 to 2627 Hz (fig. 48B). The dominant harmonic varies from the first to sixth (rarely the second harmonic), but it is usually the first ( Fig. 42G , 48B, D ). There is a clear shift in relative energy between the bands; the dominant frequency gets higher toward the end of the call, starting at the first harmonic, moving to the fifth and ending at the sixth; thenceforth it decreases, usually skipping the fifth and ending at the third or second harmonic ( Fig. 42G , 48B, D ). Most of the call energy is between 450 and 2650 Hz (four to six harmonics). The call has a general downward FM ( Fig. 48B, D ). Additionally, 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 ( Fig. 48B ), and a short downward FM at the end ( Fig. 48B, D ). 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 48. Call A of Physalaemus santafecinus. Oscillograms (A and C) and audiospectrograms (B and D). A typical call (A–B). A variant call with a different envelope and spectral features (C–D). Note the different slopes in the FM segments (D). Horizontal scale bars have 0.1 s; vertical scale bars have 1 kHz. Filter bandwidth (Hz): 84.6 (B and D).