Historias de vida y demografía de Physalaemus biligonigerus (Anura: Leptodactylidae) en una charca periurbana del centro de Argentina / Demography and life histories of Physalaemus biligonigerus (Anura: Leptodactylidae) in a peri-urban pond in central Argentina

Resumen El conocimiento de la dinámica de poblaciones provee información sobre la historia reciente, el estado actual y la tendencia futura de una población. Physalaemus biligonigerus es un anuro con una amplia distribución en el Neotrópico, presenta una actividad reproductiva elevada y explosiva, pero sus poblaciones parecen estar compuestas por individuos jóvenes. El objetivo de este estudio fue analizar la demografía poblacional de P. biligonigerus en una charca semipermanente en Río Cuarto, Córdoba, Argentina y realizar una proyección poblacional a 30 generaciones. Se determinó la estructura de edad utilizando esqueletocronología, y posteriormente se construyó una tabla de vida estática. Se calculo la fecundidad y las tasas de supervivencia para cada estadío con los que se construyó una Matriz de Leslie y se realizó la proyección poblacional. La proyección muestra oscilaciones en el número de individuos pero a pesar de esto, la tendencia final de la población es a un aumento en su tamaño. La mayor proporción de supervivientes se da en las fases de huevos a larvas, y la fuerza de mortalidad actúa con intensidad sobre la fase de larvas. La tasa neta reproductiva indica que la población de P. biligonigerus de la charca en estudio está en incremento.

Abstract Knowledge of population dynamics provides information on the recent history, current status, and future trends of a population. Physalaemus biligonigerus is widely distributed in the Neotropics, this anuran has a high and explosive reproductive activity, but its populations seem to be composed of young individuals. The objective of this study was to analyze the population demography of P. biligonigerus in a semipermanent pond in Río Cuarto, Córdoba, Argentina and to carry out a population projection through 30 generations. The age structure was determined from the use of skeletochronology, and a static life table was later made. Fertility and survival rates were calculated for each stage, by which a Leslie Matrix was constructed and the population projection was performed. The projection shows oscillations in the number of individuals but in spite of this, the final tendency of the population is an increase in its size. The highest proportion of survivors occurs in the egg-to-larval stages and the mortality force acts intensively on the larval phase. The net reproductive rate indicates that the population of P. biligonigerus of the study pond is increasing. Rev. Biol. Trop. 66(2): 765-775. Epub 2018 June 01.

Signaling Pathways in Insulin- and IGF-I Mediated Oocyte Maturation in Lower Vertebrates.

The endocrine control of oocyte maturation in fish and amphibians has proved to be a valuable model for investigating the rapid and non-genomic steroid actions at the cell surface. Considerable progress has made over the last decade in elucidating signaling pathways in steroid-induced oocyte maturation. In addition to steroids, various growth factors have also been reported to be involved in this process and progress being made to elucidate their mechanism of actions. Exposure of fully-grown oocytes to steroids or growth factors (insulin/IGFs) initiates various signaling cascade, leading to formation and activation of maturation-promoting factor (MPF), a key enzyme that catalyzes entry into M-phase of meiosis I and II. Whereas the function of MPF in promoting oocyte maturation is ubiquitous, there are differences in signaling pathways between steroids- and growth factors-induced oocyte maturation in amphibian and fish. Here, we have reviewed the recent advances on the signaling pathways in insulin- and IGF-I-induced oocyte maturation in these two groups of non-mammalian vertebrates. New findings demonstrating the involvement of PI3 kinase and MAP kinase in induction of oocyte maturation by insulin and IGF-I are presented.

Composição e diversidade de répteis Squamata na região sul do Parque Nacional Grande Sertão Veredas, Brasil Central / Diversity and composition of squamate reptiles in the southern portion of Grande Sertão Veredas National Park, Central Brazil

Neste estudo são apresentados os resultados de amostragem de Squamata do Parque Nacional Grande Sertão Veredas, MG, na área nuclear do Cerrado brasileiro, através de metodologia padronizada. A riqueza, diversidade e distribuição das espécies são comentadas e comparadas com os resultados em outras regiões do Cerrado. A fauna de Squamata na região inclui pelo menos 50 espécies, dentre as quais 25 lagartos, três anfisbenas e 22 serpentes, distribuídas em 12 famílias: Polychrotidae (1), Tropiduridae (3), Scincidae (4), Teiidae (3), Gymnophthalmidae (6), Anguidae (1), Amphisbaenidae (3), Anomalepididae (1), Leptotyphlopidae (1), Boidae (2), Colubridae (16) e Viperidae (2). A riqueza registrada e estimada indica que a região pode figurar entre as mais ricas em todo o Cerrado. As espécies de Squamata parecem possuir preferências previsíveis sobre os diferentes hábitats disponíveis, e admite-se a grande influência de fatores histórico-filogenéticos na distribuição espacial das espécies. A fisionomia do carrasco destacou-se por abrigar duas espécies restritas à região, Stenocercus quinarius e Psilophthalmus sp., sendo promissora para novos estudos. Os ambientes abertos, especialmente as fisionomias savânicas típicas do Cerrado, apresentaram maior riqueza, em concordância com outros locais estudados, e com implicações diretas na conservação da diversidade biológica do Cerrado.

We present the results of an inventory of squamate reptiles from Grande Sertão Veredas National Park region, in the Brazilian Cerrado hotspot. We used standardized sampling methods to provide richness, diversity and distribution data and compared our results with those from other Cerrado localities. The regional squamate fauna is composed of at least 50 species, of which 25 lizards, three amphisbaenians and 22 snakes, distributed in 12 families: Polychrotidae (1), Tropiduridae (3), Scincidae (4), Teiidae (3), Gymnophthalmidae (6), Anguidae (1), Amphisbaenidae (3), Anomalepididae (1), Leptotyphlopidae (1), Boidae (2), Colubridae (16) e Viperidae (2). Recorded and estimated richness indicates that the region can be one of the richest in the Brazilian Cerrado. The recorded species present predictable abundance variations among different available habitats, a probable result of the influence of phylogenetic factors in the spatial distribution of the species. The "carrasco" habitat was distinguished for harboring two restricted species to the region: Stenocercus quinarius and Psilophthalmus sp., and should receive further attention in future studies. The open habitats, especially the typical open physiognomies of Cerrado, present the highest richness levels, in agreement with results in other Cerrado localities, a fact with direct implications for the conservation of central Brazilian savannas.

Anfíbios e répteis do Parque Nacional da Serra da Bodoquena, Mato Grosso do Sul, Brasil / Amphibians and reptiles of the Serra da Bodoquena National Park, Mato Grosso do Sul, central Brazil

O Estado de Mato Grosso do Sul situa-se na porção mediana da grande diagonal de formações abertas da América do Sul, uma região que abriga uma grande diversidade de anfíbios e répteis, sendo algumas endêmicas. Apesar de sua importância biogeográfica, essa diagonal tem sido pouco considerada em estudos com abrangência regional. Dentre os componentes fitofisionômicos que compõem essa região e cuja representatividade se faz presente no Estado, as matas estacionais deciduais são elementos marcantes na região da Serra da Bodoquena. Devido a peculiaridade desse ambiente, muitas áreas ainda necessitam de uma maior avaliação quanto à sua biodiversidade. Informações sobre a herpetofauna do Parque Nacional da Serra da Bodoquena são escassas e pontuais e sugerem uma semelhança com a fauna de cerrado. Este trabalho apresenta registros da herpetofauna do Parque Nacional da Serra da Bodoquena e regiões de entorno, abrangendo áreas em bom estado de conservação e locais com atividade agropecuária. As amostragens foram realizadas em dois períodos, contemplando as estações seca e chuvosa na região. O inventário consistiu em busca ativa limitada por tempo, além de registros oportunísticos. Informações sobre a riqueza de espécies da herpetofauna da Caatinga, Cerrado e Chaco foram compiladas da literatura e comparadas com aquela registrada no presente trabalho. Foram registradas 63 espécies, sendo 38 anfíbios e 25 répteis. Muitas das espécies estavam associadas a ambientes particulares, como matas de galeria e afloramentos rochosos. A maior similaridade da herpetofauna do Parque Nacional da Serra da Bodoquena deu-se com aquela encontrada no Cerrado, provavelmente porque a área está inserida nesse bioma. Considerando-se a diversidade de hábitats da área, provavelmente o número de espécies deverá aumentar com a realização de novos inventários na região. Agregar novas informações sobre a herpetofauna da Serra da Bodoquena é fundamental para o plano de manejo...

The State of Mato Grosso do Sul, central Brazil, is located in the center of the broad South American open-dry diagonal areas. This region harbors a great diversity of amphibians and reptiles, with some endemic species. Despite such biogeographical scenario, biodiversity of this region is poorly known at local scales. Dry forests are important physiognomies in Mato Grosso do Sul and represent an important landscape element at Serra da Bodoquena, resulting in local characteristics that require biodiversity surveys. There are few and punctual information on the herpetofauna from the Serra da Bodoquena National Park and they suggest a similarity with the Cerrado herpetofauna. The present study represents the first record of the herpetofauna from the Serra da Bodoquena National Park and adjacent areas. Samples were conducted in pristine and disturbed areas in two distinct climatic periods, covering both rainy and dry seasons, by means of active search limited by time as well as opportunistic records. Data on the herpetofauna of the Caatinga, Cerrado, and Chaco biomes were compiled and compared with the species sampled in the present study. We registered 63 species, including 38 amphibians and 25 reptiles. Several species were associated to particular habitats, such as gallery forests or rocky outcrops. The herpetofauna from the Serra da Bodoquena National Park showed a greater similarity with that of the Cerrado, probably because the area is inserted in this biome. Considering the habitat diversity found at Serra da Bodoquena, the number of species must increase with other surveys in the area. Natural history and ecological studies on amphibian and reptiles of the Serra da Bodoquena must be encouraged in order to contribute for the National Park management.

Biogeography and conservation of the herpetofauna of the Upland Pine-Oak Forests of Honduras / Biodiversidad y conservación de la herpetofauna de los Bosques de Pino-Roble de la Altiplanicie de Honduras

The upland pine-oak forest herpetofauna constitutes the smallest segment distributed in the major habitat types in Honduras, due to its occurrence at moderate elevations in relatively inhospitable environments, compared to more mesic habitats in the country. This segment, however, is subject to considerable environmental threat as a consequence of annual burning and logging. Of the 356 herpetofaunal species known from Honduras, 105 are known from these habitats. These forests occur throughout much of the mountainous interior of Honduras. They are subject to the Intermediate Dry climate. Four salamanders, 27 anurans, four turtles, 29 lizards, and 41 snakes comprise the herpetofauna. These species are partitioned into restricted, widespread, and peripheral distributional categories. They can be allocated to eleven broad distributional categories, with most belonging to the category containing species whose ranges extend from somewhere in Mexico north of the Isthmus of Tehuantepec to somewhere in South America. The large majority are terrestrial forest inhabitants, arboreal forest inhabitants, terrestrial pondside species, or terrestrial forest pondside species. Most species are judged common, with the next largest group considered to be of infrequent occurrence, and the smallest group of rare occurrence. Upland pine-oak forest species are distributed among four ecophysiographic areas, with the greatest number of species being found in the Southeastern Uplands. Construction of a CBR diagram illustrates that the herpetofaunas of the Northwestern and Northeastern Uplands, the Northeastern Uplands and Southeastern Uplands, and the Southeastern Uplands and Southwestern Uplands are about equally related to one another. The greatest significance of the upland pine-oak forest herpetofauna lies in the relatively high percentage of members presently possessing stable populations, indicating their apparent greater ability to resist anthropogenic habitat...

La herpetofauna de los bosques de pino-roble del altiplano constituye el segmento más pequeño distribuido en los habitats principales de Honduras, debido a su ocurrencia a elevaciones moderadas en ambientes relativamente inhóspitos, especialmente comparados a los ambientes más húmedos de país. Este segmento, sin embargo, está sujeto a una amenaza ambiental considerable, debido a las quemas anuales y a la tala de árboles. De las 356 especies de herpetofauna conocidas en Honduras, 105 son de estos habitats. Esta clase de bosques es prevalente en gran parte del interior montañoso de Honduras. Están sujetos al clima Seco Intermedio. La herpetofauna consiste de 4 salamandras, 27 anuros, cuatro tortugas, 29 lagartijas, y 41 serpientes. Estas especies se clasifican en categorías de distribución restrictas, extensas, y periféricas. Es posible colocar estas especies en once categorías de distribución, con la mayoría encontrándose en la categoría que contiene las especies cuyos rangos se extienden desde alguna parte de México al norte del Istmo de Tehuantepec hasta alguna parte de Suramérica. La gran mayoría son habitantes terrestres del bosque, habitantes arbóreos del bosque, especies terrestres de la orilla de estanques de agua, o especies terrestres del bosque encontradas a la orilla de estanques de agua. La mayoría de las especies se consideran comunes, con el próximo grupo más grande considerado como de ocurrencia poco frecuente, y el grupo más pequeño de rara ocurrencia. Las especies de bosques de pino y roble del altiplano están distribuidas en cuatro áreas ecofisiográficas, con el mayor número de especies encontradas en los altiplanos del sureste. La creación de un diagrama de Coeficientes de Semejanza Biogeográfica (CBR por sus siglas en inglés) ilustra que la herpetofauna de los altiplanos del noroeste y del nordeste, la de los altiplanos del nordeste y del sureste, y la de los altiplanos del sureste y del suroeste, están relacionadas...