Review of bioacoustical traits in the genus Physalaemus Fitzinger, 1826 (Anura: Leptodactylidae: Leiuperinae)
Author
Hepp, Fábio
Author
Pombal, José P.
text
Zootaxa
2020
2020-01-20
4725
1
1
106
journal article
24303
10.11646/zootaxa.4725.1.1
67d90a4f-f853-4561-ae9a-c0f596d948ca
1175-5326
3612996
B137F19A-2C50-476C-8F13-4F049253B361
Physalaemus gracilis
(Boulenger, 1883)
We found a single call
type
for the species, referred to as call A. The call is composed of a single harmonic note, with general downward FM, but with an up-downward FM segment in the first sixth of the call.
Call A (
Fig. 50
A–T and 52A).
We examined 40 recordings, a total of 158 minutes, with
ca
. 2480 calls from
106 males
. Only some of these calls were measured (see
Table 2
). Call duration varies from 0.451 to
0.565 s
. The envelope of the call is variable (
Fig. 50A
, C–G, M–P). In most calls, rise and fall are similar in duration and shape (exponential) and the sustain is long. Some sustains are regular (
Fig. 50A, G, M, N, O
) and others are irregular, with short and shallow valleys, mainly at the beginning of the segment (
Fig. 50D, F, P
). In several calls, the sustain has a convex shape and the limits between the call rise, sustain, and call fall are not clear. Usually, the envelope is divided into two parts with different amplitude levels (
Fig. 50C
). The amplitude peak is usually at the end of the first seven tenths of the call duration. The envelope varies from elliptic or rectangular (
Fig. 50A, D, F, G, M, N, O
) to triangular (pointed left;
Fig. 50C, E, P
). Due to the asymmetry of some triangular envelopes, the shape resembles an arrow. More than 50 % of the call energy is concentrated in 32 % of the call duration around the amplitude peak. There is no PAM in the call. The call has a harmonic series (
Fig. 52A
). The fundamental frequency is
ca.
510 Hz and approximately the first seven harmonics are emphasized. The wave periods are regular and harmonics are clear throughout the call. Subharmonics (f
0
1/2 and f
0
1/3) are common at the beginning and middle of the call (
Fig.
50I
, L, Q, R
). The dominant frequency varies from
ca
.
2110 to 2760
Hz (
Fig. 50B
). The dominant harmonic varies from the first to the seventh (except the second), but it is usually the fourth, fifth, or sixth (
Fig. 52A
). 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 third, fourth, fifth and sixth, and ending at the sixth or seventh; thenceforth, the dominant frequency decreases in some calls, moving to the fourth harmonic (
Fig. 52A
,
50B
). Most of the call energy is between 950 and 3050 Hz (four to five harmonics). The call has a general downward FM (
Fig. 50B
, H–L, Q–T). Additionally, calls have an up-downward FM in the first sixth of the call duration, leading to slightly arc-shaped bands in this part of the call, and a short downward FM at the end (
Fig. 50B
, H–L, Q–T). The general downward FM and the initial up-downward FM result in S-shaped harmonics when considering the entire call. Some calls have a slight PFM (
Fig. 50H, I, L
).