Physalaemus atlanticus Haddad & Sazima, 2004

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 : 52

Physalaemus atlanticus Haddad & Sazima, 2004

We found a single call type for the species, referred to as call A. The call has a single harmonic note with a sequence of pulses (pulse-PAM). Pulses of this call can have subharmonics.

Call A ( Fig. 20 A–F and 13G). We examined six recordings, a total of 15 minutes, with ca. 450 calls from ten males. Only some of these calls were measured (see Table 2 ). Call duration varies from 1.096 to 1.377 s. In most calls, the limits between the call rise, sustain, and fall are not clear (for example in calls with elliptic envelope; see below). When perceptible, the call rise and fall of the call are similar in duration and shape, both with a logarithmic or linear shape, and there is a long and regular sustain. The amplitude peak is at around the middle of the call duration ( Fig. 20A ). The envelope varies from elliptic ( Fig. 20A ) to rectangular ( Fig. 20C ), depending on how emphasized or regular is the sustain. More than 50 % of the energy is concentrated in 38 % of the call duration around the amplitude peak. This call has a strong PAM (with silence intervals present between pulses; Fig. 20 A–F). The rate of the PAM is ca. 48 Hz, forming ca. 60 pulses throughout the call. The pulse rise is shorter than the fall and the amplitude peak is at their outset ( Fig. 20D ). In most calls, the last pulse is the longest (ca. four times the duration of the other pulses). Silence intervals are present between pulses, which is approximately as long as the pulses ( Fig. 20D ). The call has a harmonic series ( Fig. 13G ). The fundamental frequency is ca. 440 Hz and is generally absent in the audiospectrograms. The wave periods are regular and harmonics are clear throughout the call. However, the short duration of the pulses makes the bands broad with narrow intervals. Longer pulses have subharmonics (usually f 0 1/2). The dominant frequency varies from ca. 950 to 1380 Hz ( Fig. 20B ). The dominant harmonics varies between the second and third, but it is usually the second. There is no clear shift in the relative energy among the bands throughout the call. Most of the energy is concentrated between 900 and 1500 Hz (two harmonics). Some calls have a slight upward general FM ( Fig. 20B, E ). Most calls have neither general FM nor other additional FM in the call.

Figures

FIGURE 13. Multiplicity relationship between “instantaneous” dominant frequency and w of calls A of eight Physalaemus species. Each graph shows a single call A of: P. nanus (A), P. spiniger (B), P. crombiei (C), P. signifer (D), P. bokermanni (E), P. angrensis (F), P. atlanticus (G), P. moreirae (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. nanus; A).

FIGURE 20. Call A of Physalaemus atlanticus. Oscillograms (A, C, and D) and audiospectrograms (B, E, and F). A single typical call with elliptic envelope (A and B). Variant call with different envelope and general FM (C and E). Last pulses of the call (D and F). Horizontal scale bars have 0.1 s; vertical scale bars have 1 kHz. FFT (points): 750 (F); 1024 (B and E).