Reassessment of the advertisement call of topotypic Scinax squalirostris (Anura: Hylidae), with an acoustic evaluation of its occurrence in the Serra da Mantiqueira, southeastern Brazil

Abstract

Reassessment of the advertisement call of topotypic Scinax squalirostris (Anura: Hylidae), with an acoustic evaluation of its occurrence in the Serra da Mantiqueira, southeastern Brazil. Scinax squalirostris (Lutz, 1925) is thought to occur along a broad range in South America. The values reported for calls of topotypes differ substantially among studies. Because vocalizations often play a key role in uncovering cryptic diversity, the call of S. squalirostris is herein redescribed based on a new sample of topotypes. The call of a population from Poços de Caldas, Minas Gerais state, is also described. Topotypic advertisement calls have a dominant frequency between 3970 and 4125 Hz; 13–15 notes emitted at a rate of 24–27/s; call rate of 67/min and duration of 0.52–0.61 s; mid-call notes having 6 or 7 well-defined pulses, and an intra-note pulse rate of 223–266/s. Calls of the Poços de Caldas population have dominant frequency between 4083 and 4358 Hz; 15–18 notes emitted at a rate of 32–34/s; call rate of 64/min and duration of 0.46–0.56 s; mid-call notes having 6 or 8 well-defined pulses, and an intra-note pulse rate of 252–312/s. The advertisement calls of these populations have some differences with each other, and are promptly distinguished from calls of morphologically similar species. Our data to topotypes are inconsistent with some previously reported. A more detailed study of the population from Poços de Caldas is required, and more marked differences may be found in populations more distant from type locality of S. squalirostris.

Predicting impacts of global climatic change on genetic and phylogeographical diversity of a Neotropical treefrog

“…The reduction in suitable areas and the decline of amphibian species within PAs due to climate change are of major concern in conservation planning (Loyola et al., 2008, 2014; Vasconcelos et al., 2018). Scinax squalirostris ’ populations from Central‐West and Southeast Brazil have distinct morphological and acoustic characteristics compared with populations from South Brazil (Faria et al., 2013; Giaretta et al., 2020; Pombal et al., 2011). Our findings show that populations from the Central‐West and Southeast Brazil have lower genetic diversity and will have lower suitability in the EOC.…”

Neogene–Quaternary tectonic, eustatic and climatic events shaped the evolution of a South American treefrog

“…Scinax squalirostris (Lutz, 1925) is a small (23–28 mm, Cei, 1980) hylid treefrog, widely distributed in grasslands of South America, from central, southeast and southern Brazil towards northern Bolivia, southern Paraguay, Uruguay and northeastern Argentina (Frost, 2021; Giaretta et al, 2020). Although its geographical distribution is continuous across different ecoregions, such as Pampas, Uruguayan Savanna and the Humid Chaco, it is spatially disjoint at high altitudes, in the sky‐islands of the Atlantic Forest and at the Cerrado ecoregions (Giaretta et al, 2020).…”

“…Scinax squalirostris (Lutz, 1925) is a small (23–28 mm, Cei, 1980) hylid treefrog, widely distributed in grasslands of South America, from central, southeast and southern Brazil towards northern Bolivia, southern Paraguay, Uruguay and northeastern Argentina (Frost, 2021; Giaretta et al, 2020). Although its geographical distribution is continuous across different ecoregions, such as Pampas, Uruguayan Savanna and the Humid Chaco, it is spatially disjoint at high altitudes, in the sky‐islands of the Atlantic Forest and at the Cerrado ecoregions (Giaretta et al, 2020). Scinax squalirostris is commonly found vocalising or hidden perched on herbaceous or shrub vegetation throughout its distribution (Cochran, 1955; Eterovick & Sazima, 2004), and it is considered a cryptic anuran species due to differences in its acoustic call parameters (Faria et al, 2013; Giaretta et al, 2020).…”

“…Although its geographical distribution is continuous across different ecoregions, such as Pampas, Uruguayan Savanna and the Humid Chaco, it is spatially disjoint at high altitudes, in the sky-islands of the Atlantic Forest and at the Cerrado ecoregions (Giaretta et al, 2020). Scinax squalirostris is commonly found vocalising or hidden perched on herbaceous or shrub vegetation throughout its distribution (Cochran, 1955;Eterovick & Sazima, 2004), and it is considered a cryptic anuran species due to differences in its acoustic call parameters (Faria et al, 2013;Giaretta et al, 2020). Because of this wide and disjoint geographical distribution encompassing distinct biogeographical regions and ecoregions, under different climates and elevations, S. squalirostris represents a suitable model to identify and understand how past geological and climatic events could have generated intraspecific genetic variation at different temporal and geographical scales.…”

Posição taxonômica de duas populações relacionadas à >i<Scinax squalirostris>/i< (Lutz, 1925) (Anura: Hylidae)

“…(2020) que forneceram uma detalhada recaracterização de seu canto topotípico (ver seção Anexo). Substanciais diferenças interpopulacionais têm sido reportadas para essa espécie no que diz respeito ao canto de anúncio (Haddad et al, 1988;Pombal Jr. et al, 1995Faria et al, 2013;Leite et al, 2019;Giaretta et al, 2020), e algumas diferenças no tamanho e morfologia de adultos (B. Lutz, 1952aLutz, ,b, 1973Cochran, 1955;Gallardo, 1961;Haddad et al, 1988;Pombal Jr. et al, 2011) e girinos (Klappenbach & Langone, 1992;Silva, 2020;Pezzuti et al, 2021) também foram relatadas.…”