First record of Scinax centralis (Anura, Hylidae) in the Triângulo Mineiro region, state of Minas Gerais, southeastern Brazil, with further data on its vocalization

Abstract Scinax comprises more than 120 species which are split in two clades, the S. ruber and the S. catharinae clades. A few species within the S. catharinae clade occur in gallery forests of the Brazilian Cerrado. We here extend the distribution of S. centralis southwards based on new populations sampled in the banks of the Rio Paranaíba, in the borders of Minas Gerais (MG) and Goiás (GO) states, southeastern Brazil. We also provide further data on the species vocalization. Variation was seen among our population and topotypes regarding SVL and call dominant frequency, both likely representing a clinal variation. Our new population of S. centralis represents the first record of the species for the state of Minas Gerais.

First record of Scinax centralis (Anura, Hylidae) in the Triângulo Mineiro region, state of Minas Gerais, southeastern Brazil, with further data on its vocalization

Abstract Scinax comprises more than 120 species which are split in two clades, the S. ruber and the S. catharinae clades. A few species within the S. catharinae clade occur in gallery forests of the Brazilian Cerrado. We here extend the distribution of S. centralis southwards based on new populations sampled in the banks of the Rio Paranaíba, in the borders of Minas Gerais (MG) and Goiás (GO) states, southeastern Brazil. We also provide further data on the species vocalization. Variation was seen among our population and topotypes regarding SVL and call dominant frequency, both likely representing a clinal variation. Our new population of S. centralis represents the first record of the species for the state of Minas Gerais.

First record of Scinax centralis (Anura, Hylidae) in the Triângulo Mineiro region, state of Minas Gerais, southeastern Brazil, with further data on its vocalization

Scinax comprises more than 120 species which are split in two clades, the S. ruber and the S. catharinae clades. A few species within the S. catharinae clade occur in gallery forests of the Brazilian Cerrado. We here extend the distribution of S. centralis southwards based on new populations sampled in the banks of the Rio Paranaíba, in the borders of Minas Gerais (MG) and Goiás (GO) states, southeastern Brazil. We also provide further data on the species vocalization. Variation was seen among our population and topotypes regarding SVL and call dominant frequency, both likely representing a clinal variation. Our new population of S. centralis represents the first record of the species for the state of Minas Gerais.(AU)

Breeding activity of Scinax centralis (Anura, Hylidae) in Central Brazil

From January, 1997 to April, 1998, we studied breeding activity in a population of Scinax centralis Pombal & Bastos, 1996, in the state of Goiás, inside the Cerrado Biome, Brazil. The behavior of males and females in the choruses, the relationships between environmental variables and the presence of individuals, the spatial distribution pattern, amplexus and clutches were analyzed. The breeding season occurred from November to May. The majority of males began to call when they entered the chorus; they were defending their calling sites against other males. We found a positive correlation between the number of females and males in the choruses, but no significant correlation was observed between the operational sexual ratio (OSR, number of reproducing females/number of reproducing males) and the number of calling males. OSR was highly male-biased; on average, there were 40 males for each female. The presence of individuals was positively correlated with air temperature of two previous days and negatively correlated with rainfall on the observation day. Generally, males were non-randomly distributed and satellite males were observed. Females were larger and heavier than males. Egg number, but not diameter of the egg, was correlated with the female size.

Entre janeiro de 1997 e abril de 1998, estudou-se a atividade reprodutiva em uma população de Scinax centralis Pombal & Bastos, 1996 no estado de Goiás, no bioma Cerrado, Brasil. Analisou-se o comportamento de machos e fêmeas nos agregados reprodutivos, as relações entre variáveis ambientais e a presença de indivíduos, o padrão de distribuição espacial, amplexos e desovas. A estação reprodutiva ocorreu de novembro a maio. A maioria dos machos começou a vocalizar quando entrou nos agregados; defendendo seus sítios de canto contra outros machos. Nós encontramos uma correlação positiva entre o número de fêmeas e de machos presentes no coro, mas não entre a razão sexual operacional (RSO, número de fêmeas reprodutivas/número de machos reprodutivos). A RSO foi altamente desviada para os machos; em média, haviam 40 machos para cada fêmea. A presença de indivíduos foi correlacionada positivamente com a temperatura do ar dos dois dias anteriores e negativamente correlacionada com a chuva do dia da observação. Geralmente, a distribuição espacial dos machos era uniforme. Machos satellites foram observados. As fêmeas eram maiores e mais pesadas que os machos. O número de ovos, mas não o diâmetro, está correlacionado com o tamanho da fêmea.

Breeding activity of Scinax centralis (Anura, Hylidae) in Central Brazil

From January, 1997 to April, 1998, we studied breeding activity in a population of Scinax centralis Pombal & Bastos, 1996, in the state of Goiás, inside the Cerrado Biome, Brazil. The behavior of males and females in the choruses, the relationships between environmental variables and the presence of individuals, the spatial distribution pattern, amplexus and clutches were analyzed. The breeding season occurred from November to May. The majority of males began to call when they entered the chorus; they were defending their calling sites against other males. We found a positive correlation between the number of females and males in the choruses, but no significant correlation was observed between the operational sexual ratio (OSR, number of reproducing females/number of reproducing males) and the number of calling males. OSR was highly male-biased; on average, there were 40 males for each female. The presence of individuals was positively correlated with air temperature of two previous days and negatively correlated with rainfall on the observation day. Generally, males were non-randomly distributed and satellite males were observed. Females were larger and heavier than males. Egg number, but not diameter of the egg, was correlated with the female size.

Entre janeiro de 1997 e abril de 1998, estudou-se a atividade reprodutiva em uma população de Scinax centralis Pombal & Bastos, 1996 no estado de Goiás, no bioma Cerrado, Brasil. Analisou-se o comportamento de machos e fêmeas nos agregados reprodutivos, as relações entre variáveis ambientais e a presença de indivíduos, o padrão de distribuição espacial, amplexos e desovas. A estação reprodutiva ocorreu de novembro a maio. A maioria dos machos começou a vocalizar quando entrou nos agregados; defendendo seus sítios de canto contra outros machos. Nós encontramos uma correlação positiva entre o número de fêmeas e de machos presentes no coro, mas não entre a razão sexual operacional (RSO, número de fêmeas reprodutivas/número de machos reprodutivos). A RSO foi altamente desviada para os machos; em média, haviam 40 machos para cada fêmea. A presença de indivíduos foi correlacionada positivamente com a temperatura do ar dos dois dias anteriores e negativamente correlacionada com a chuva do dia da observação. Geralmente, a distribuição espacial dos machos era uniforme. Machos satellites foram observados. As fêmeas eram maiores e mais pesadas que os machos. O número de ovos, mas não o diâmetro, está correlacionado com o tamanho da fêmea.