Allometric escape from acoustic constraints is rare for frog calls.

Allometric constraint is a product of natural selection and physical laws, particularly with respect to body size and traits constrained by properties thereof, such as metabolism, longevity, and vocal frequency. Allometric relationships are often conserved across lineages, indicating that physical constraints dictate scaling patterns in deep time, despite substantial genetic and ecological divergence among organisms. In particular, acoustic allometry (sound frequency ~ body size) is conserved across frogs, in defiance of massive variation in both body size and frequency. Here, we ask how many instances of allometric escape have occurred across the frog tree of life using a Bayesian framework that estimates the location, number, and magnitude of shifts in the adaptive landscape of acoustic allometry. Moreover, we test whether ecology in terms of calling site could affect these relationships. We find that calling site has a major influence on acoustic allometry. Despite this, we identify only four major instances of allometric escape, potentially deriving from ecomorphological adaptations to new signal modalities. In these instances of allometric escape, the optima and strength of the scaling relationship are different than expected for most other frog species, representing new adaptive regimes of body size ~ call frequency. Allometric constraints on frog calls are highly conserved and have rarely allowed escape, despite frequent invasions of new adaptive regimes and dramatic ecomorphological divergence. Our results highlight the rare instances in which natural and sexual selection combined can overcome physical constraints on sound production.

The aggressive call of Dendropsophus cruzi (Pombal Bastos, 1998) (Anura; Hylidae) in Central Brazil.

Dendropsophus cruzi (Pombal Bastos, 1998) is a small hylid (male snout-to-vent length = 16.3-19.4 mm; female SVL = 21.3-25.0 mm) that is allocated in the D. microcephalus group (Faivovich et al. 2005). It is commonly found in Open and forested areas from Central Brazil to Provincia Velasco, Departamento de Santa Cruz, Bolivia (Frost 2017; Tessarolo et al. 2016). Pombal Bastos (1998) described the advertisement call of D. cruzi as a single pulsed note. Posteriorly, studies uncovered relationships between dominant frequency variation in the advertisement calls of D. cruzi and variation in the SVL and mass of males (Bastos et al. 2003), as well as the existence of a clinal geographic pattern in the variation of acoustic parameters of these calls (Tessarolo et al. 2016). However, the acoustic communication in anurans is usually mediated by more than one vocalization type (Toledo et al. 2015). Due the importance of call types in the social context of anurans (e.g., Reichert 2011; Forti et al. 2017), we expand the vocal repertoire of D. cruzi by describing its aggressive call.

The advertisement calls of Brazilian anurans: Historical review, current knowledge and future directions.

Advertisement calls are often used as essential basic information in studies of animal behaviour, ecology, evolution, conservation, taxonomy or biodiversity inventories. Yet the description of this type of acoustic signals is far to be completed, especially in tropical regions, and is frequently non-standardized or limited in information, restricting the application of bioacoustics in science. Here we conducted a scientometric review of the described adverstisement calls of anuran species of Brazil, the world richest territory in anurans, to evaluate the amount, standard and trends of the knowledge on this key life-history trait and to identify gaps and directions for future research strategies. Based on our review, 607 studies have been published between 1960 to 2016 describing the calls of 719 Brazilian anuran species (68.8% of all species), a publication rate of 10.6 descriptions per year. From each of these studies, thirty-one variables were recorded and examined with descriptive and inferential statistics. In spite of an exponential rise over the last six decades in the number of studies, described calls, and quantity of published metadata, as revealed by regression models, clear shortfalls were identified with regard to anuran families, biomes, and categories of threat. More than 55% of these species belong to the two richest families, Hylidae or Leptodactylidae. The lowest percentage of species with described calls corresponds to the most diverse biomes, namely Atlantic Forest (65.1%) and Amazon (71.5%), and to the IUCN categories of threat (56.8%), relative to the less-than-threatened categories (74.3%). Moreover, only 52.3% of the species have some of its calls deposited in the main scientific sound collections. Our findings evidence remarkable knowledge gaps on advertisement calls of Brazilian anuran species, emphasizing the need of further efforts in standardizing and increasing the description of anuran calls for their application in studies of the behaviour, ecology, biogeography or taxonomy of the species.

The advertisement call and geographic distribution of Proceratophrys dibernardoi Brandão, Caramaschi, Vaz-Silva & Campos 2013 (Anura, Odontophrynidae).

Proceratophrys dibernardoi Brandão, Caramaschi, Vaz-Silva & Campos 2013 has recently been described and allocated into the P. cristiceps species group, but no information about its advertisement calls has been provided (Brandão et al. 2013). Here, we describe for the first time the advertisement calls of P. dibernardoi based on specimens from Central Brazil. We also expand P. dibernardoi´s geographic distribution by reporting a new population in the State of Mato Grosso do Sul, Brazil, constituting the westernmost record for this species, and extending its known range approximately 330 km westward of the municipality of Aporé, State of Goiás (P. dibernardoi´s former westernmost record).

Anfíbios anuros associados a corpos d'água do sudoeste do estado de Goiás, Brasil / Anuran amphibians associated to water bodies in Southwest of Goiás State (Brazil)

O Cerrado é o segundo maior bioma brasileiro e é considerado um dos mais importantes hotspots de biodiversidade. Neste bioma foram registradas cerca de 150 espécies de anuros, das quais 30 por cento são endêmicas. Entretanto, existem muitas áreas ainda não inventariadas, nas quais não se conhece quase nada sobre a diversidade de anuros. Assim, neste estudo apresentamos informações referentes a anurofauna do sudoeste do Estado de Goiás (Brasil Central), a qual vem sendo modificada principalmente pela agropecuária. Nesta região, 45 corpos d'água foram amostrados entre os meses de novembro/2007 a fevereiro/2008 e novembro/2008 a março/2009, localizados próximos a plantações de soja, cana-de-açúcar, pastagem e vegetação nativa. No total, foram registrados adultos e girinos de 36 espécies de anuros, a maioria comum de áreas abertas. As curvas de acumulação de espécies, tanto para adultos quanto para girinos, apresentaram a formação de uma assíntota, o que indica uma baixa probabilidade de registro de novas espécies mesmo com a amostragem de outros corpos d'água. Nesta área com forte influência de impactos agrícolas, a riqueza encontrada representa aproximadamente 1/4 do total de espécies conhecidas para o bioma Cerrado.

The Cerrado is the second largest biome in Brazil and is considered one of most important among the biodiversity hotspots. In this biome can be found about 150 anurans species, from which 30 percent are endemic. However, there are many Cerrado areas that have little information gathered about the anuran biodiversity. Thus, in this study we present the result of an inventory of anurans species from the southwest region of Goiás State (Central Brazil). In this region, we sampled 45 water bodies, located near soybean and sugar-cane cultures, pastures and natural vegetation, from November/2007 to February/2008 and from November/2008 to March/2009. Altogether, adults and tadpoles of 36 species were registered, with the majority of species registered in association to open areas. The rarefied curve of species richness show an asymptote formation, which indicates that the chance to add species to the inventory is low, even with additional habitats sampling. Therefore, our results reveal high species richness in the present sampled region, which represented almost one fourth of all species found in Cerrado.