Redescription of the advertisement call of Brachycephalus tridactylus (Anura: Brachycephalidae)

Marcos R. Bornschein; Mario M. Rollo Jr.; Marcio R. Pie; André E. Confetti; Luiz F. Ribeiro

doi:10.7287/peerj.preprints.27243v1

Redescription of the advertisement call of Brachycephalus tridactylus (Anura: Brachycephalidae)

Marcos R. Bornschein ^1,2, Mario M. Rollo Jr.¹, Marcio R. Pie^2,3, André E. Confetti⁴, Luiz F. Ribeiro^2,5

1 Instituto de Biociências, Universidade Estadual Paulista, São Vicente, São Paulo, Brazil

2 Mater Natura - Instituto de Estudos Ambientais, Curitiba, Paraná, Brazil

3 Departamento de Zoologia, Universidade Federal do Paraná, Curitiba, Paraná, Brazil

4 Programa de Pós-Graduação em Zoologia, Universidade Federal do Paraná, Curitiba, Paraná, Brazil

5 Escola de Ciências da Vida, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil

DOI: 10.7287/peerj.preprints.27243v1

Published: 2018-09-28
Accepted: 2018-09-28

Subject Areas: Animal Behavior, Zoology
Keywords: bioacoustics, note-centered approach, isolated notes, Brazilian Atlantic Forest

Copyright: © 2018 Bornschein et al.
Licence: This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.

Cite this article: Bornschein MR, Rollo Jr. MM, Pie MR, Confetti AE, Ribeiro LF. 2018. Redescription of the advertisement call of Brachycephalus tridactylus (Anura: Brachycephalidae) PeerJ Preprints 6:e27243v1 https://doi.org/10.7287/peerj.preprints.27243v1

Abstract

Background. Brachycephalus includes miniaturized frogs with restricted geographical distributions throughout the Brazilian Atlantic Forest. Ecological data for most species are still scarce. For instance, advertisement calls have only been described for 12 of the 36 known species, including B. tridactylus, a recently described species from southern Brazil. Posteriorly, features of the advertisement call of B. tridactylus were compared with congeners and the unique characteristics of its call were highlighted. To confirm these potentially divergent characteristics, we reanalysed an original recording of B. tridactylus and analysed our own recordings and verified that the original description of its advertisement call is inaccurate. Thus, we redescribe its advertisement calls.

Methods. We asked the descriptors of B. tridactylus the original recordings that they made and requested access to the only original recording deposited in a collection of sounds. We received from André Lima a copy of one recording, the same as the one that had deposited, and obtained permission to re-analyze it. We studied this recording and compared it with our own recordings, made at the type locality of the species on March, 2016. Sound samples were analysed with Raven Pro 1.5.0 and call analyses were made under a note-centered approach.

Results. The original recording was amplified somehow by at least 6 dB and was also clearly low-pass filtered with a cutoff frequency of 10 kHz. Our analyses did not allow us to recognize several of the acoustic parameters normally described in Brachycephalus. The sound we heard from the notes overlapped with other signals (noise?), which prevented us from clearly determining the end of the note and other important features, such as the presence of pulses. According to our recordings (n = 15 individuals), B. tridactylus emitted a relatively long advertisement call (50.8 s, on average), composed by 10–13 notes emitted in a note rate of 3.7–8.3 notes per minute. Only isolated notes were present. The notes were composed by 1–3 pulses and the note duration varied from 0.002–0.021 s.

Discussion. The original description of the call of B. tridactylus is incorrect because it included background noise and amplification artefacts as part of the call parameters. However, we recognize that the original recording and our recordings have captured the same type of call. In our measurements of the species calls, note duration was nearly an order of magnitude shorter as the original description. The existence of notes with 1–3 pulses was not acknowledged in the original description. With few pulses per notes, the advertisement call of B. tridactylus is distinct from the notes with several pulses of B. ephippium, B. pitanga, B. crispus, B. sulfuratus, and B. darkside. The advertisement calls of B. tridactylus is also distinct from that of B. albolineatus and B. mirissimus by having only isolates notes, instead of isolated notes and note groups.

Author Comment

This is a submission to PeerJ for review.

Supplemental Information

035_Brachycephalus_tridactylus_individual_01_collected_MHNCI_10294_by_MR_Bornschein

036_Brachycephalus_tridactylus_individual_02_not_collected_by_MR_Bornschein

037_Brachycephalus_tridactylus_individual_03_example_01_not_collected_by_MR_Bornschein

038_Brachycephalus_tridactylus_individual_03_example_02_not_collected_by_MR_Bornschein

039_Brachycephalus_tridactylus_individual_03_example_03_not_collected_by_MR_Bornschein

040_Brachycephalus_tridactylus_individual_04_example_01_collected_CFBH-individual_05_by_MR_Bornschein

041_Brachycephalus_tridactylus_individual_04_example_02_collected_CFBH-individual_05_by_MR_Bornschein

42_Brachycephalus_tridactylus_individual_05_collected_CFBH-individual_06__by_MR_Bornschein

043_Brachycephalus_tridactylus_individual_06_collected_CFBH-individual_07_by_MR_Bornschein

44_Brachycephalus_tridactylus_individual_07_not_collected_by_MR_Bornschein

045_Brachycephalus_tridactylus_individual_08_not_collected_by_MR_Bornschein

046_Brachycephalus_tridactylus_individual_09_collected_MHNCI_10730_by_MR_Bornschein

047_Brachycephalus_tridactylus_individual_10_not_collected_by_MR_Bornschein

048_Brachycephalus_tridactylus_individual_11_and_individual_12_not_collected_by_LF_Ribeiro_10_III_16

049_Brachycephalus_tridactylus_individual_13_not_collected_by_LF_Ribeiro_10_III_16

050_Brachycephalus_tridactylus_individual_14_not_collected_by_LF_Ribeiro_10_III_16

051_Brachycephalus_tridactylus_individual_15_not_collected_by_LF_Ribeiro_10_III_16