NORTH-WESTERN JOURNAL OF ZOOLOGY 13 (2): 271-277 ©NwjZ, Oradea, Romania, 2017 Article No.: e161511 http://biozoojournals.ro/nwjz/index.html A reassessment of the advertisement call of Ischnocnema parva (Anura: Brachycephalidae) Felipe Silva de ANDRADE1,2,3,*, Isabelle Aquemi HAGA1 and Ariovaldo Antonio GIARETTA1 1. Laboratório de Taxonomia, Sistemática e Ecologia de Anuros Neotropicais. Faculdade de Ciências Integradas do Pontal, Universidade Federal de Uberlândia (UFU), CEP 38304-402, Campus Pontal, Ituiutaba, Minas Gerais, Brasil 2. Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, CEP 13083-970, Campinas, São Paulo, Brasil 3. Programa de Pós-Graduação em Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, CEP 13083-970. Campinas, São Paulo, Brasil * Corresponding author, F.S. de Andrade, E-mail: [email protected] Received: 11. April 2016 / Accepted: 20. October 2016 / Available online: 24. November 2016 / Printed: December 2017 Abstract. Ischnocnema parva is a small species that occurs in the leaf litter within the Atlantic Forest in southeastern Brazil. The advertisement call of this species was described in the early 90’s based on an undefined number of males from Estação Biológica da Boracéia in the municipality of Salesópolis, state of São Paulo. In this study, based on data from four localities in two Brazilian states, we re-describe the advertisement call of I. parva which consists of a single type of pulsed note emitted sporadically with its fundamental frequency peaking at about 2000 Hz and its dominant frequency peaking at about 4000 Hz. The calls of males from two localities have a higher pulse rate and longer interpulse interval. Compared to our data, the call previously described in literature has a higher pulse rate and lower dominant frequency. In addition, we interpret that the species call has a harmonic structure and a distinct amplitude modulation from the previously reported. Key-words: Atlantic forest, bioacoustics, Terrarana, taxonomy, vocalization. neiro (RJ), and it is widely distributed in the At- Introduction lantic Forest of southeastern Brazil (Siqueira-Jr et al. 2004, Giaretta & Facure 2008, Cruz et al. 2009, The Terrarana genus Ischnocnema Reinhardt & Martins et al. 2010, Frost 2015). Brusquetti et al. Lütken comprises 33 species, which occur from (2013), based on molecular evidence, suggest that Central and southern Brazil to adjacent northern more than one species may be hidden under this Argentina with most species associated to the name. coastal Brazilian Atlantic Forest (Canedo & Heyer et al. (1990) briefly described the adver- Haddad 2012, Frost 2015). Based on molecular tisement call of Ischnocnema parva from the Estação evidence, most Ischnocnema species are currently Biológica de Boracéia, municipality of Salesópolis, arranged into four species series: I. guentheri, I. lac- state of São Paulo. Herein we describe calls of I. tea, I. parva, and I. verrucosa (Canedo & Haddad parva from several localities in southeastern Brazil, 2012, Padial et al. 2014). Ischnocnema manezinho as well as discuss the remarkable differences (Garcia, 1996) and I. sambaqui (Castanho & found between our samples and those previously Haddad, 2000) are unassigned to species series published. Our study can help future works on (Padial et al. 2014). The Ischnocnema parva species revealing the real diversity under the name I. series has only three species, whereas other spe- parva. cies series include up to 10 species (Canedo & Haddad 2012, Brusquetti et al. 2013, Padial et al. 2014). Material and Methods Ischnocnema parva (Girard, 1853), I. pusilla (Bo- Bioacoustics kermann, 1967), and I. nanahallux Brusquetti, We recorded 26 males and analyzed 91 calls. Fourteen Thomé, Canedo, Condez & Haddad, 2013 com- males (48 calls) from the Parque Municipal do Itapetin- prise the I. parva species series (Padial et al. 2014). inga, municipality of Atibaia (23°9’4.72’’S, 46°31’17.19’’W, The last two are only known from their type lo- 1000 m a.s.l.; Mantiqueira mountain range) on 15 October calities (cf. Bokermann 1967, Brusquetti et al. 2013) 2013 and 02 November 2015, air temperature 1822 °C; and no data is available on their advertisement five males (11 calls) from the municipality of Salesópolis (23°37’52.65’’S, 45°55’17.32’’W; 860 m a.s.l.; Serra do Mar calls. Ischnocnema parva was described from the mountain range) on 28–29 December 2015, 2123 °C; two municipality of Rio de Janeiro, state of Rio de Ja- males (2 calls) from the municipality of Ubatuba 272 F.S. de Andrade et al. Figure 1. Geographic distribu- tion of the members of the Ischnocnema parva species se- ries. Municipalities labeled: green circles (our samples): 1—municipality of Atibaia (SP), 2—municipality of Salesópolis (SP), 3—municipality of Ubatuba (SP), 4—municipality of Rio Preto (MG); black triangles (type localities): 5—municipality of Santa Maria Madalena (RJ – I. nanahallux), 6—municipality of Rio de Janeiro (RJ – I. parva), 7—municipality of São José do Barreiro (SP – I. pusilla). Brazilian states ac- ronyms: São Paulo = SP, Minas Gerais = MG; and Rio de Janeiro = RJ. (23°21’52.16’’S, 44°58’13.14’’W; 165 m a.s.l.; Serra do Mar maximum values for all call sample variation. For each mountain range) on 20 July 2009 and 29 October 2010, 19 analyzed call, we measured all of its pulse/interpulse in- °C; all these localities are in the state of São Paulo (SP), tervals. Brazil (Fig. 1). We also recorded five males (30 calls) from In order to compare with our samples from Salesópo- the municipality of Rio Preto (21°58’33.001’’S, lis, we generated an oscillogram and corresponding spec- 43°54’10.014’’W; 1390 m a.s.l.; Serra Negra mountain trogram (with the same settings aforementioned) of ad- range) on 05–06 November 2015, 19–24°C, state of Minas vertisement call attributed to I. parva by Heyer et al. Gerais (MG), Brazil (Fig. 1). (1990). The audio file in wav format is available as sup- Voucher specimens are deposited in the Frogs Col- plemental material at Frogs of Boracéia: Online Audio lection of the Universidade Federal de Uberlândia (AAG- Supplement UFU), municipality of Uberlândia (MG); and in the am- <http://vertebrates.si.edu/herps/frogs_boraceia/list.ht phibian collection of the Museu de Zoologia of the Uni- m>. versidade Estadual de Campinas (ZUEC), municipality of Campinas (SP), under the following numbers: AAG-UFU Statistical analysis 52035204, 5412; and ZUEC 2321223214. We searched for eventual discrimination among popula- Calls were recorded with a ME67/K6 Sennheiser di- tions by applying two functions on R software: (1) "Ran- rectional microphone connected to a Marantz PMD-670 or dom Forest" (RF) (radomForest package, Liaw & Wiener Marantz PMD-671, or with a ME66/K6 Sennheiser direc- 2002), and (2) “dapc” (adegenet package, see Jombart tional microphone connected to a Boss BR-864, or M- 2008, Jombart et al. 2010). Random Forest algorithm con- audio Microtrack II. Calls were obtained at sampling rate structs many (e.g. 1000) classification trees using boot- of 44.1 kHz and sample size of 16 bit. We analyzed calls strap samples from the original dataset and then gener- using Raven Pro 1.5, 64-bit version (Bioacoustics Research ates classifiers and aggregates results by voting to classes Program 2014) with the following settings: window type (Breiman 2001); the OOB (out-of-bag) data was used to = Hann; window size = 256 samples; 3 dB filter band- get an unbiased estimate of the classification error as trees width = 248 Hz; brightness = 50%; contrast = 50%; over- are added to the forest (Breiman 2001). lap = 85% (locked); DFT size = 1024 samples (locked); Traditional Discriminant Analysis (DA) depends on grid spacing (spectral resolution) = 43.1 Hz. Temporal multivariate normality (Pohar et al. 2004) and on a larger traits were measured on oscillograms and the spectral number of objects than variables. The multivariate nor- ones on spectrograms. We measured the peaks of funda- mality assumption was tested through the function mental (selecting only the lower band on spectrograms) "mardiaTest" (MVN package, Korkmaz et al. 2014) on R and others frequency bands through “Peak Frequency software and we found that our data were not multivari- (Hz)” function, and the frequency values with 5 and 95% ate normal (details not shown). We applied DA on a few of energy of the call were obtained automatically by the axes (preserving about 95% of the variance) of a Principal program through its “Frequency 5% (Hz)” and “Fre- Component Analysis, as performed by “dapc”, which quency 95% (Hz)” functions, respectively. We generated improves the imbalance between objects and variables call figures using Seewave v.1.6 package (Sueur et al. (Jombart et al. 2010). The results of "dapc" were evaluated 2008) on R version 3.2.3 (R Core Team 2015). Seewave set- within an exploratory context and to assess their congru- tings were: Hanning window, 85% overlap and 512 points ence in relation to those from "Random Forest". resolution (FFT). The nomenclature and definitions of the We used the following acoustic variables for the sta- acoustic structures follow McLister (1995) (see their Table tistical analyses: call duration, call rise time, pulses per 2). We calculated means and standard deviations (SD) for note, pulse duration, interpulse interval, pulse rate, peak each individual and then the overall mean and SD was of the dominant frequency, minimum of the dominant calculated based on those values (Gerhardt and Huber frequency, and maximum of the dominant frequency. 2002); whereas the range encompassed the minimum and Considering that both multivariate analyses were highly Call of Ischnocnema parva 273 Table 1. Measurements of the advertisement call of Ischnocnema parva from several localities in southeast Brazil (see text for details).