643 resultados para CHORUS FROGS PSEUDACRIS


Relevância:

10.00% 10.00%

Publicador:

Resumo:

A new species of the tree toad genus Dendrophryniscus is described from a rainforest habitat at Parque Nacional de Serra das Lontras, municipality of Arataca, southern Bahia, Brazil. Dendrophryniscus oreites sp. nov. is related to the Atlantic forest brevipollicatus group by hand morphology, skin texture, ventral coloration and bromelicolous habits. The new species differs from related species by having a larger size, warty skin, inner finger reduced with presence of a dark nuptial pad in males, and a yellowish coloration with discrete dorsal pattern. This discovery highlights the importance of southern Bahia in terms of conservation, and for our understanding of the evolution of the frog diversity within the Atlantic Rainforest.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We describe the advertisement call, tadpole, karyotype, and additional information on the natural history of Cycloramphus lutzorum from southern Brazil. Sonograms were generated from digitally recorded calls. Tadpoles were collected in the field for description in the lab, and an adult was collected for karyotyping. Data on seasonal activity were gathered monthly from November 2005 to November 2007. All tadpoles (N = 21), juveniles (N = 18), and adults (N = 52) were found exclusively in streams. Reproduction, as identified by calling frogs, occurred from July through November. Frogs call all day long, but mostly at dusk, from rock crevices inside the stream edges near the splash zone. The call is short and loud, with 11 pulsed notes, of 491-641 ms, with a dominant frequency of 0.98-1.39 kHz. We describe the exotrophic and semiterrestrial tadpoles, always found in constantly humid vertical rock walls in the stream. Tadpoles of C. lutzorum are recognized by differences in labial tooth row formula, eye diameter, body shape, position of nares, and development of tail. Like congeneric species, the karyotype of C. lutzorum comprises 26 metacentric and submetacentric chromosomes. Cycloramphus lutzorum is restricted to and adapted for living in fast flowing streams, many of which are threatened by deforestation, pollution, and habitat loss. Therefore, we recommend the status of C. lutzorum be changed from its current ""Data Deficient"" to ""Near Threatened (NT)"" in the IUCN species red list.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Analysis of the phylogenetic relationships among trypanosomes from vertebrates and invertebrates disclosed a new lineage of trypanosomes circulating among anurans and sand flies that share the same ecotopes in Brazilian Amazonia. This assemblage of closely related trypanosomes was determined by comparing whole SSU rDNA sequences of anuran trypanosomes from the Brazilian biomes of Amazonia, the Pantanal, and the Atlantic Forest and from Europe, North America, and Africa, and from trypanosomes of sand flies from Amazonia. Phylogenetic trees based on maximum likelihood and parsimony corroborated the positioning of all new anuran trypanosomes in the aquatic clade but did not support the monophyly of anuran trypanosomes. However, all analyses always supported four major clades (An01-04) of anuran trypanosomes. Clade An04 is composed of trypanosomes from exotic anurans. Isolates in clades An01 and An02 were from Brazilian frogs and toads captured in the three biomes studied, Amazonia, the Pantanal and the Atlantic Forest. Clade An01 contains mostly isolates from Hylidae whereas clade An02 comprises mostly isolates from Bufonidae; and clade An03 contains trypanosomes from sand flies and anurans of Bufonidae, Leptodactylidae, and Leiuperidae exclusively from Amazonia. To our knowledge, this is the first study describing morphological and growth features, and molecular phylogenetic affiliation of trypanosomes from anurans and phlebotomines, incriminating these flies as invertebrate hosts and probably also as important vectors of Amazonian terrestrial anuran trypanosomes.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Antimicrobial peptides (AMPs) are essential for the innate immune system of eukaryotes, imparting protection against pathogens and their proliferation in host organisms. The recent interest in AMPs as active materials in bionanostructures is due to the properties shown by these biological molecules, such as the presence of an alpha-helix structure and distribution of positive charges along the chain. In this study the antimicrobial peptide dermaseptin 01 (DS 01), from the skin secretion of Phyllomedusa hypochondrialis frogs was immobilized in nanostructured layered films in conjunction with nickel tetrasulfonated phthalocyanines. The leishmanicidal activity of DS 01 was confirmed using kinetic essays, in which DS 01 promoted death of all metacyclic promastigote cells in 45 minutes. Surprisingly, the immobilized DS 01 molecules displayed electroactivity, as revealed by electrochemical experiments, in which an oxidation peak at about 0.61 V was observed for a DS 01 monolayer deposited on top of a conductive electrode. Such electroactivity was used to investigate the sensing abilities of the nanostructured films toward Leishmania. We observed an increase in the oxidation current as a function of number of Leishmania cells in the electrolytic solution at concentrations down to 10(3) cells/mL. The latter is indicative that the use of AMPs immobilized in electroactive nanostructured films may be of interest for applications in the pharmaceutical industry and diagnosis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

What is my dance now? My body is saturated with images and details. My choreography has become an exorcism of ghosts of “opening-nights past” as I dance out memories and events inscribed on my body. A chorus of my other selves now accompanies my stage performance, live and virtual, real and imagined, past and present.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Wesley Enoch’s Black Medea is explicit about what is, and what is not, its project: the chorus implores the audience not to read the narrative of its infanticidal heroine as one that demonises black women. Instead, the play affirms that its narrative can be understood differently and in a way that has a wider social significance. Taking my cue from the claim that the story is somehow ‘about everyone,’ I would like to begin unravelling the play’s relevance to contemporary contentions of Australian and indeed ‘Unaustralian’ subjectivity, particularly in relation to the discourses that seek to construct ‘Australian’ identity through an appeal to antiquity and what I describe as ‘the archaic.’ It seems to me that Black Medea presents an opportunity for thinking about the ways in which the discourses of aboriginal and classical antiquity operate to inform contemporary, contesting definitions of Australian identity. Regardless of whether these discourses of antiquity are claimed as ‘Australian’ or abjected as Other or ‘Unaustralian’ – and they have been used in both ways – they remain, I argue, formative to current conceptions of Australian identity and are positioned in the economy of discourses that comprise that arena. As will be seen, the mixed reception or ambivalence with which these complementary discourses of antiquity are treated in Australian culture gives Black Medea the potential to be situated among them in subversive and questioning ways, and in ways that may highlight the reasons for their ambivalent status.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Go-Betweens recorded six albums that are among the finest work of the 1980s, earning them a reputation as ""the ultimate cult band"" and the lasting esteem of their peers, from R.E.M. to Sleater-Kinney. In 2000 they returned to making records--and received the best reviews of their career. David Nichols relates their story with wit and verve, and since the Go-Betweens had personalities as well as talent, their biography is compelling reading, not just for committed fans but for anyone interested in the current music scene.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

What is my dance now? My body is saturated with images and details. My choreography has become an exorcism of ghosts of “opening-nights past” as I dance out memories and events inscribed on my body. A chorus of my other selves now accompanies my stage performance, live and virtual, real and imagined, past and present.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We evaluated the effect of ambient temperatures between 25 and 43°C on the rate of evaporative water loss (EWL) in eight adult Litoria xanthomera (average body mass = 7.3 ± 0.6 g). Frogs were placed in a cylindrical chamber that permitted them to fully conceal their ventral surfaces using a water-conserving posture. Their EWL was 7.1 ± 0.7 mg g–1 h–1 at 25°C and reached 28.0 ± 2.5 mg g–1 h–1 at 43°C. Agar replicas of the frogs were used to evaluate boundary-layer resistances associated with the EWL measurements and, thus, to permit evaluation of cutaneous resistance to vapour diffusion (rc) in live frogs. The rc of L. xanthomera was stable over the temperature range of 25–35°C, averaging about 28 s cm–1, and then declined stepwise with ambient temperatures above 37°C. The highest rc recorded for each individual over the range of temperatures studied averaged 32.0 ± 1.2 s cm–1. The thermolabile nature of rc demonstrates a well developed thermoregulatory control of EWL in this species, a trait very similar in pattern and extent to that previously measured in the closely related Litoria chloris.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We investigated changes in the spatial organization of individuals within a population of endangered Southern Bell Frogs Litoria raniformis over an eight-month period. Our results identified strong temporal changes in both spatial organization and the apparent location of L. raniformis within the study site. Ripley's K Function analyses showed that the position of individuals relative to one another shifted from random immediately after the study site was flooded (p < 0.005), to strongly clustered at spatial scales between 0-1 500 m during the peak breeding period (p < 0.005). The majority of flooded areas were dry by April and May and individuals again became aggregated within the remaining waterbodies.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This note documents a predation event on a juvenile Blotched Bluetongue Lizard (Tiliqua nigrolutea) by a Highlands Copperhead (Austrelaps ramsayi) in the Blue Mountains, Australia.  The diet of elapid snakes in the genus Austrelaps consists mainly of frogs and small skinks. Adults of the larger Tiliqua species may be too large for Austrelaps species to consume, and juveniles of these larger Tiliqua are possibly approaching the larger end of consumable prey items for Austrelaps.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

and on is a short instrumental featuring a nylon stringed acoustic guitar with an echo, chorus and tap reverb added to the tail, piano, and two synth pads.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

and on is a short instrumental featuring a nylon stringed acoustic guitar with an echo, chorus and tap reverb added to the tail, piano, and two synth pads.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Despite frequent reliance on surveys to document public attitudes towards conservation issues (such as invasive-species control), only rarely do researchers assess the validity of statements made by the public in response to such surveys. Therefore, how well responses match actual behaviour remains an open question. We conducted a survey asking drivers if they had seen and/or run over (intentionally or not) snakes, native frogs or invasive cane toads (Rhinella marina) on roads in the Northern Territory of Australia. To compare actual driver behaviour to the survey responses, we also carried out field experiments where we quantified the rates at which model snakes, frogs and toads (and controls) were run over on a rural highway. Our results show a discrepancy between survey responses and driver behaviour: for example, 25% of the people we surveyed indicated that they intentionally run over cane toads, yet field experiments showed that model toads were run over no more frequently than expected by chance, or than any other type of model.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Although interest in the ecological impacts of invasive species has largely focused on negative effects, some native taxa may benefit from invader arrival. In tropical Australia, invasive cane toads (Bufo marinus) have fatally poisoned many native predators (e.g., marsupials, crocodiles, lizards) that attempt to ingest the toxic anurans, but birds appear to be more resistant to toad toxins. We quantified offtake of dead (road-killed) cane toads by raptors (black kites (Milvus migrans) and whistling kites (Haliastur sphenurus)) at a site near Darwin, in the Australian wet-dry tropics. Raptors readily took dead toads, especially small ones, although native frogs were preferred to toads if available. More carcasses were removed in the dry season than the wet season, perhaps reflecting seasonal availability of alternative prey. Raptors appeared to recognize and avoid bufotoxins, and typically removed and consumed only the toads’ tongues (thereby minimizing toxin uptake). The invasion of cane toads thus constitutes a novel prey type for scavenging raptors, rather than (as is the case for many other native predators) a threat to population viability.