Luciana Signorelli

Distribuição temporal e diversidade de modos reprodutivos de anfíbios anuros no Parque Nacional das Emas e entorno, Estado de Goiás, Brasil

The communities of anuran amphibians, especially in tropical regions, are directly influenced by environmental conditions, whfich play an important role in structuring and regulating communities. This study aimed to determine the diversity of reproductive modes, season of vocalization and to test correlation among climatic variables and richness, abundance of adult frogs and tadpoles, and activity of vocalization of males in 12 water bodies located in and around the Emas National Park, southwestern state of Goias, Brazil. Sixteen samples were carried out between December 2005 and March 2008. A total of 25 species from five families were recorded: Bufonidae (one species), Hylidae (nine species), Leptodactylidae (eight species), Leiuperidae (six species) and Microhylidae (one species). Four patterns of reproductive activity were recognized among the species: continuous, intermediate, long and explosive. The richness of adult frogs, the abundance and activity of the calling males were positively related to air temperature, humidity and precipitation. The richness of tadpoles was positively related to precipitation and water temperature, but there was no relationship between the abundance of tadpoles with no descriptors of climate. Six reproductive modes were recorded, 56% of species had widespread aquatic reproductive modes (mode 1 and 4) and 44% deposit eggs in nests of foam (modes 11, 13, 30 and 32). The species recorded in this study showed a predominance of reproductive modes and general reproductive pattern typically associated with the warm and rainy period, as expected for tropical and seasonal regions. However, the temporal segregation between groups of species within the rainy season seems to facilitate the coexistence of generalist species typical of open and/or anthropogenic areas.

A New Miniature Treefrog of the Scinax ruber Clade from the Cerrado of Central Brazil (Anura: Hylidae)

Abstract We describe a new species of treefrog of the Scinax ruber clade related to Scinax fuscomarginatus from southwest of the state of Goiás in central Brazil. The new species is characterized by its small size (snout–vent length of males, 15.9–18.6 mm; females, 18.1–18.7 mm), very slender body, a snout that is strongly acute in lateral view and subelliptical in dorsal view, two lateral broad blackish stripes from the posterior corner of the eye to inguinal region, reduced toe webbing, and advertisement calls that are a single pulsed note with a pulse period of 2–13 ms and a dominant frequency of 2.51–5.95 kHz. Vocalizations of the new species and S. fuscomarginatus, Scinax parkeri, Scinax squalirostris, and Scinax wandae are provided and discussed.

Individual variation in the advertisement calls of a Neotropical treefrog (Scinax constrictus)

Studies of the variability of signals at different levels are important to resolve issues related to the evolution of a species’ recognition system. We analysed the variation within males, among individuals, and among three breeding seasons in the advertisement calls of Scinax constrictus, a Neotropical hylid frog endemic to the Cerrado of Brazil. We assessed the influence of different temperature ranges and different body condition ranges over a three-year period of breeding season on the acoustical features of the advertisement calls of 62 individuals. Air temperature had negative relationship with call duration and note number. Body condition had a negative relationship with the dominant frequency and positive effects on pulse number and note duration. The acoustic parameters of S. constrictus were stable across breeding seasons. Temporal parameters were highly variable within individuals, whereas the dominant frequency was the most stereotyped property of advertisement calls. Individuals of S. constrictus have sufficient among-male variability, especially for temporal parameters (call duration, number of notes, and note duration), to permit discrimination between conspecific calling males at a reproductive site by statistical analysis. The results highlight the informativeness of non-invasive bioacoustic features for population-level studies and biological conservation.

Advertisement Calls of Three Anuran Species (Amphibia) from the Cerrado, Central Brazil

ABSTRACT. Aspects of natural history, such as the advertisement call, of many frog species from central Brazil are unknown. This kind of vocalization is important for specific recognition, thus studies describing these calls are needed. Herein we describe the advertisement calls of three anuran species from the Cerrado Biome: (a) Allobates goianus (Aromobatidae); (b) Odontophrynus salvatori (Cycloramphidae); (c) Lysapsus caraya (Hylidae). From October to December/2001 and March/2009, the vocalizations of individuals of these species were recorded in three municipalities in Goiás state: Alto Paraíso, Araguapaz and Silvânia. The advertisement calls emitted by A. goianus presented modulation of frequency and those vocalizations emitted by O. salvatori and L. caraya showed pulsioned structure. In general, these species presented advertisement calls different from those emitted by other species in the same genus. This difference reinforces the importance of the advertisement calls for specific recognition and also the validity of these species.

Predation on Frogs by the Introduced Crab Dilocarcinus pagei Stimpson, 1861 (Decapoda, Trichodactylidae) on a Neotropical Floodplain

In general, amphibians are numerous and small-sized, and the gregarious behaviour of most species in the breeding season makes them potential prey for many different predators (Duellman & Trueb, 1994). Most predation occurs near or in the water (Toledo, 2005) in the breeding season, when the majority of species enter the water and consequently become accessible to potential aquatic predators (Bastos et al., 1994; Haddad & Bastos, 1997; Toledo, 2003). Among these predators are several species of freshwater and forest crabs, which can predate on the tadpoles (Gray & Christy, 2000) and frogs (Hayes, 1983), or at least mutilate their limbs or digits (Duellman & Trueb, 1994; Gray et al., 2002). Freshwater crabs are important organisms in food webs of tropical environments, where they act as detritivores or primary and secondary consumers, and can become either predators on, or prey for, other invertebrates (Hayes, 1983; Dobson et al., 2002; Marijnissen et al., 2009; Klaus & Plath, 2011). Sublethal attacks normally occur when the predators are similar in size to, or smaller than, their prey (Schoener, 1979). Gray et al. (2002) stated that the most likely cause of injuries in frogs is attack by invertebrates such as ants, crabs, or spiders, which are neither prey nor predators but share the same habitat. The extensive floodplain of the Upper Paraná River contains many smaller rivers, canals, lakes and ponds, and wetlands, where a common feature is the presence of large patches of macrophytes (Pelicice et al., 2008). Macrophytes provide amphibians with shelter and refuge, but they also increase the incidence of predators (Denton & Beebee, 1997; Laurila, 1998), such as the crab Dilocarcinus pagei Stimpson, 1862 (cf. Magalhães et al., 2005).

Vocalizations of Hypsiboas goianus (Lutz, 1968) (Anura: Hylidae) in Central Brazil

ABSTRACT Environmental and morphological factors and social context influence the vocalizations of anuran species. Herein, we observed the acoustic behavior of Hypsiboas goianus males from Central Brazil and analyzed the following calls: advertisement, short aggressive and long aggressive. The acoustic parameters of advertisement calls were not correlated with air temperature, mass or snout–vent length; however, the acoustic parameters of short aggressive calls were influenced by these variables. The temporal parameters of advertisement and short aggressive calls were classified as dynamic properties, while the dominant frequency was considered a static property. Dominant frequency is the most important variable to discriminate calls among individuals.

Amphibia, Anura, Hylidae, Scinax pusillus Pombal, Bilate, Gambale, Signorelli & Bastos, 2011: Distribution extension

Scinax pusillus is endemic to the Cerrado biome in Brazil and restricted to the state of Goias from where the species was originally described. Herein, we report the first record of Scinax pusillus in Brazilian protected areas, update its distribution in the state of Goias, and present the first record for the state of Mato Grosso do Sul.

Reptilia, Squamata, Tropiduridae, Stenocercus sinesaccus Torres–Carvajal, 2005: distribution extension

The present study reports the easternmost known record for the tropidurid lizard Stenocercus sinesaccus Torres–Carvajal, 2005, at Floresta Nacional de Silvânia, state of Goias, Brazil, in a transition area between cerrado sensu strictu and gallery forest.