Abstract in English:We studied the thermal ecology and thermoregulatory behavior of Coleodactylus natalensis Freire, 1999 in a remnant of a northern coastal patch of the Brazilian Atlantic Forest. Data were collected during four 20-day field excursions over the course of one year. We assessed the importance of substrate and air temperatures, in addition to time of exposure to sunlight, as relevant factors for the regulation of body temperature in this species. After each specimen was captured, body (Tb), substrate (Ts) and air (Ta) temperature were measured 10 cm above the ground, using a temperature sensor coupled to a fast response thermo-hygrometer. Ad libitum and focal animal methods were used to describe thermoregulatory behavior. The mean body temperature of C. natalensis was 31.3 ± 3°C (amplitude of 26.9 and 38.4°C, n = 20). A positive relationship was found between Tb and environmental temperatures; further, substrate temperature explained the additional variability of temperature variations in this species. With respect to environmental observations, individuals of C. natalensis did not expose themselves directly to the sun, moving equally between full and filtered sun. Our results indicate that C. natalensis is umbrophylic and a passive thermoregulator.
Abstract in English:Understanding what influences the activity of organisms is important for both ecological understanding and species conservation. Using data from 2,707 camera trap days distributed across 24 forest sites, we present quantitative analyses of the activity pattern of Cuniculus paca (Linnaeus, 1766) in southern Amazonia. We compared the activity pattern of this species across four designated subsets of the 24-hours diel cycle (dawn, dusk, day and night). Using linear regression models we tested the influence of season, temperature and rainfall on the activity patterns of C. paca (paca). We also evaluated the nocturnal photos of paca (N = 111) as a function of the degree of lunar illumination in order to test the prediction that pacas minimize their activity during moon phase when illumination is brighter. Pacas were not recorded during the day but were active at dawn, dusk and night time. We found differences in the influence of the abiotic variables on the nocturnal activity of pacas in the study area. There was no significant difference between the observed (expressed as the frequency of total counts of independent photos over the five classes of lunar illumination) and the expected activity of pacas, based on the frequency of days in the lunar cycle with different classes of lunar illumination, whereas lunar illumination had a weak negative influence on the timing of paca activity (i.e. pacas were active closer to sunset with increasing lunar illumination). However, the timing of nocturnal activity in pacas was not influenced by season, temperature or rainfall. Our findings highlight the ecological plasticity of this Neotropical rodent which has a key function in the maintenance of Neotropical forests.
Abstract in English:We collected and analyzed 286 Barn owl, Tyto alba (Scopoli, 1769), pellets from two nests in different environments along the mid-Araguaia River in central Brazil. Our analyses revealed that these owls feed mainly on small mammals, especially rodents. Owls from the riverbanks at Fazenda Santa Fé had a more diverse diet, preying mainly on rodents that typically inhabit riparian grasslands - Holochilus sciureus Wagner, 1842 - and forests - Hylaeamys megacephalus (Fischer, 1814) and Oecomys spp., which probably also occur in forest borders or clearings. On the other hand, owls from an agroecosystem at Fazenda Lago Verde preyed mostly on rodent species common in these agrarian fields, Calomys tocantinsi Bonvicino, Lima & Almeida, 2003. Additionally, we compared small mammal richness estimates based on the analysis of owl pellets with estimates from live-trapping in the same areas. Owl pellets revealed two rodent species undetected by live traps - Euryoryzomys sp. and Rattus rattus (Linnaeus, 1758) - and four rodent species were trapped, but not found in owl pellets - Oecomys roberti Thomas, 1904, Pseudoryzomys simplex (Winge, 1887), Rhipidomys ipukensis Rocha, B.M.A. Costa & L.P. Costa, 2011, and Makalata didelphoides (Desmarest, 1817). Traps yielded higher species richness, but these two methods complement each other for surveying small rodents.
Abstract in English:Migration is defined as a seasonal and cyclic population movement observed in all animal classes and studied mainly in vertebrates. A considerable part of the knowledge on migration comes from birds, for which migration is an important aspect of their biology. In the case of bats, females usually migrate larger distances than males in some species. The present study analyzes the seasonal occurrence of Pygoderma bilabiatum (Wagner, 1843) at different elevations, in order to test for a pattern that evidences migration, using data from the states of Espírito Santo, Minas Gerais, Rio de Janeiro, São Paulo, Paraná, Santa Catarina, and Rio Grande do Sul, Brazil. A total of 529 specimens of P. bilabiatum were captured. Pygoderma bilabiatum seems to be more frequent at intermediate and high elevations (over 80% of all captures were made above 250 m a.s.l.) and at latitudes above 22°S, where rainfall is high (over 1,500 mm) and temperatures are mild (16-23°C). Sex ratio varied with elevation; it was skewed towards males at lower elevations (N = 9, r² = 0.60, F = 12.311, p = 0.008, Sex ratio = 0.0004*elevation + 0.976), though females predominated at all altitudinal bands and in all states analyzed.
Abstract in English:In this contribution we characterize the spatial diversity of bird populations in a heterogeneous landscape with respect to vegetation in the northern Pantanal region of Brazil. The method of additive partitioning of species diversity (γ = α + β) was used. Samples were collected in a grid with 30 sampling plots within a 25 km² area (5 x 5 km). A total of 163 bird species were found, comprising 114 resident species and 49 regional migrants. Most species were restricted spatially, with 58% found in a maximum of five sampling plots, while 15% were found in only one plot. The beta diversity comprised 77% of total diversity and was lower for residents than for regional migrants (66% and 88%, respectively). This suggests greater spatial heterogeneity in diversity patterns for regional migrants. Seasonal availability of resources caused by changing water levels as well as anthropogenic influences may also play a role in species diversity patterns by influencing species composition across sampling plots. High beta diversity and species-specific habitat occupancy suggest that conservation and management strategies should be implemented at a regional spatial scale and focus on the conservation of this environmental mosaic.
Abstract in English:In South America, one important symptom of the failure of fish passages to sustain fish migratory recruitment is the inability of eggs and larvae to reach the nurseries. This is especially so when the breeding areas are located upstream of a reservoir, and the floodplain is downstream of the dam. Therefore, the transport of fish larvae and eggs across reservoir barriers is a key factor in the development of effective conservation strategies. In this paper, we evaluate the potential for migratory fish larvae and egg transportation across a small size reservoir in eastern Brazil. We sampled fish daily between 15th October 2002 and 15th February 2003 (spawning period) in the Mucuri River, immediately upstream of the reservoir and downstream of the Santa Clara Power Plant dam. Our study was the first to indicate the possibility of successful larval passage through the reservoir of a hydroelectric reservoir and dam in South America, and showed that the passage of migratory fish larvae was associated significantly with residence time of water in the reservoir. The relatively short water residence time and elevated turbidity of the Santa Clara's reservoir waters during the rainy season certainly contributed to the successful passage, and can be considered as key factors for a priori evaluations of the feasibility of a downstream larval passage.
Abstract in English:In this study we review the records regarding occurrence of Hemidactylus mabouia Moreau De Jonnès, 1818 in Brazil, looking for records of the species in natural habitats, in order to assess the present status of this gecko as an exotic or invasive alien species in the country. We surveyed the available records of H. mabouia living in natural conditions, considering secondary data obtained from the literature, supplemented with original field records obtained by the authors during fieldwork. We found a total of 36 records in the literature and/or field records reporting the occurrence of H. mabouia in natural habitats in 36 different localities in 13 Brazilian states. The states presenting a higher number of records were Rio de Janeiro (seven), Bahia, São Paulo (six), and Espírito Santo (five different areas). We show that the invasion of Brazilian natural habitats by H. mabouia has taken place for some decades. Presently we have consistent records that it has invaded natural habitats in 13 Brazilian states. This suggests thatit is important to start monitoring H. mabouia in order to measure the rate and effectiveness of its establishment in natural habitats in Brazil and also to evaluate the potential negative effects of this invasion on sympatric species.
Abstract in English:In this study we provide the first data regarding community parameters of leaf-litter anurans inhabiting a forest floor in the state of Paraná, southern Brazil, including information on community species richness, composition, specific density and biomass. Our study was conducted at Salto Morato Natural Reserve using forty plots of 4 x 4 m for each one of the four seasons (winter, spring, summer and autumn), totaling 2.560 m² of forest floor sampled. We sampled a total of 96 frogs inhabiting the forest floor, belonging to seven species: Brachycephalus hermogenesi (Giaretta & Sawaya, 1998), Ischnocnema guentheri (Steindachner, 1864), Haddadus binotatus (Spix, 1824), Leptodactylus gr. marmoratus, Physalaemus spiniger (Miranda-Ribeiro, 1926), Proceratophrys boiei (Wied-Neuwied, 1824), and Rhinella abei (Baldissera, Caramaschi & Haddad, 2004). The overall frog density in the forest floor was 3.73 ind/100m², with I. guentheri (1.37 ind/100 m²) being the most common species and R. abei (0.19 ind/100 m²), the rarest. The estimated overall frog mass in the community was 3.29 g. The abundance, richness and density varied consistently among the four seasons sampled, with the highest values occurring in the spring and summer seasons.
Abstract in English:The Pantanal is a South American biome characterized by extensive plains and stark environmental seasonality. Several habitats are subject to annual flooding, forcing small mammal species to aggregate in dry forest patches, which most likely influences their population dynamics and life history strategies. In order to investigate the seasonal influence on the life history traits of these small mammals, we conducted a 2-year mark-recapture study in the southeastern region of the Brazilian Pantanal (Nhecolândia) and analyzed the population dynamics of the most abundant small mammal species with the jackknife estimator. A trapping effort of 21,560 trap-nights resulted in 615 individuals in 1,171 captures (success = 5.43%). Three species of rodents - Oecomys mamorae (Thomas, 1906), Thrichomys pachyurus (Wagner, 1845), and Clyomys laticeps (Thomas, 1841) - and three species of marsupials - Gracilinanus agilis (Burmeister, 1854), Thylamys macrurus (Olfers, 1818), and Monodelphis domestica (Wagner, 1842) - were obtained. The most abundant species was O. mamorae, followed by G. agilis and T. pachyurus. Oecomys mamorae was more abundant in the wet season and presented an opportunistic reproductive strategy. Gracilianus agilis displayed increased population sizes in the dry season and synchronized, seasonal reproduction during the rainy season. Thrichomys pachyurus had a small population size, delayed response to variations in environmental conditions and higher reproductive rates in the dry season. All species revealed different life history strategies (seasonal, opportunistic or delayed response to environmental variations), coinciding with periods of higher resource availability in order to maximize survival.
Abstract in English:From an ecological point of view, parasites are considered important selective forces that influence all aspects of a host's life. The purpose of this study was to assess the health state of Turdus leucomelas Vieillot, 1818 (Turdidae: Passeriformes) inhabiting a Brazilian Cerrado in the breeding and molting seasons through a hematological parameter analysis and an evaluation of infection by blood parasites. The birds were collected with mist-nets, ringed and blood sampled to assess hematological parameters (hematocrit, hemoglobin concentration and white blood cells) and blood parasites. We detected blood parasites through optical microscopy and subsequently used PCR (amplification of the 18sRNA gene) to verify the presence of Plasmodium spp. (avian malaria). During the breeding season, the hemoglobin level and CHGM percentage were greater. Global leukocyte count was positively related to hemoglobin level, CHGM percentage and body weight. Of the total 31 T. leucomelas individuals examined, 18 presented Plasmodium parasites (58% of prevalence). There was a significant relationship between the presence of Plasmodium spp. and decreased CHGM. These results suggest a connection between the health parameters of wild birds and the physiological stress associated with the breeding season.
Abstract in English:In this work we investigated the quantitative aspects of the relationship between Rhinella pombali (Baldissera, Caramaschi & Haddad, 2004) tadpoles and their trichodinid ectoparasites. Specimens were collected from a small stream located at an agricultural area between rainforest fragments in southeastern Brazil. A total of 80 tadpoles were investigated. Trichodina heterodentata Duncan, 1977 was the only trichodinid ciliate species recovered. All tadpoles were naturally infested by T. heterodentata with a mean intensity of 695.14 ± 33.33 trichodinid ciliates per tadpole. A positive correlation was observed between the intensity of the infestation and tadpole weight. Intensity of infestation did not significantly influence mean trichodinid diameter in the populations studied. This is the first study investigating density-dependent effects in interspecific interactions between trichodinids and anurans.
Abstract in English:Three species of Sidneioides Kesteven, 1909 were known until now, all of them from the western Pacific. Sidneioides peregrinus is a new species we found in Paranaguá Bay, southern Brazil. Diagnostic characteristics of the species are: colonies with 1-5 lobes, closely clumped, and attached by the entire basal area or by a common smaller area; seven to ten thin longitudinal fiber muscles (some branched) along the anterior two thirds of the thorax; no transverse muscle fibers; more than 30 tentacles of three orders forming one circle; pharynx with 10 to 12 rows of stigmata with 13 to 15 stigmata in each half row; bilobed anus at the level of the fourth or fifth row of stigmata; posterior abdomen not very elongated, oval, and joined to the abdomen by a narrow neck; numerous (> 30) testicular follicles; ovary with about 15 oocytes at about the ninth or tenth row of stigmata in the thorax; large number of embryos incubated in the atrial cavity in the right side of the thorax; larvae oval with a 0.65 mm long trunk, four club-shaped ectodermal ampullae in each side and three, linear and evenly spaced, adhesive papillae with thin stalks, two clusters of ectodermal vesicles, one postero-ventral (around 15 vesicles) and another antero-dorsal (around eight vesicles) between the ampullae and the oral siphon. This paper describes this new species and reports its occurrence in Brazil, where it is most likely introduced. The hypothesis that it is introduced is based on 1) it was never found in previous surveys, 2) in Brazil, it has a restricted and local distribution, 3) its type locality is near a major international port, and 4) the genus, prior to this description, had never been found in the Atlantic Ocean. Considering the great abundance found on the underside of natural boulders, it is imperative that S. peregrinus population growth be studied to evaluate the possibility of rapid distribution expansion.
Abstract in English:Myotis albescens (É. Geoffroy, 1806) occurs from Mexico to Uruguay and Argentina. Despite a large number of specimens in collections, its variability in South America has been underestimated, potentially leading to errors in identification. In order to clarify the taxonomic limits of M. albescens and to evaluate previous hypotheses of geographic variation in size we analyzed the type material and studied the variability in South American samples using multivariate exploratory and confirmatory procedures, as well as frequency analyses of discrete morphological data. The presence of a fringe of hairs along the trailing edge of the uropatagium, the long and silky pelage with frosted appearance on the dorsum, ear 9 to 14 mm long, broad interorbital and postorbital constrictions, and a globular braincase were identified as the most useful traits to distinguish M. albescens from its South American congeners. In agreement with Bergman's rule, larger specimens were found in the South. Beyond the geographic component, Individual variation is an important factor affecting the variability in the size and shape of the skull and pelage color.
Abstract in English:Two new species of Cyamops Melander are described, one from the Afrotropical and one from the Neotropical Region. The newly described species are (type locality in parenthesis): Cyamops mathisi sp. nov. (Province Fianarantsoa, Madagascar) and Cyamops manauensis sp. nov. (state of Amazonas, Brazil). Both species can be separated from congeners based on characters of the male genitalia, particularly the shape of the surstyli. A new country, the Ivory Coast, is added to the distribution records of Cyamops nigeriensis, previously known only from Nigeria and Namibia. Updated keys to the Afrotropical and Neotropical species of the genus are also given.
Abstract in English:Three new species of Hydroptilidae are herein described and illustrated from specimens collected with light traps in the states of Pará and Rio de Janeiro, Brazil. Flintiella carajas sp. nov., from Floresta Nacional de Carajás, shares with F. panamensis Harris, Flint & Holzenthal, 2002, F. tamaulipasa Harris, Flint & Holzenthal, 2002, F. yanamona Harris, Flint & Holzenthal, 2002, and F. manauara Santos & Nessimian, 2009 a deeply incised phallic apex. However, males can be distinguished by a ventromesal process on segment VII, by lacking dorsal hooked processes on segment IX, by the elongate subgenital plate, and by the lateral lobes of the phallic apex slightly curved laterad. Rhyacopsyche diacantha sp. nov. is closely related to R. yatay Angrisano, 1989 and R. garuhape Angrisano & Sganga, 2009. All three species have complex inferior appendages with ventral and dorsal lobes. The new species is distinguished by the male genitalia with segment X two times longer than broad, inferior appendages with the apices obliquely truncate, and a bilobed dorsal lobe on the inferior appendages. Features of the male genitalia of Rhyacopsyche angra sp. nov., R. hagenii and R. dikrosa are similar, but the first species can be distinguished by the inferior appendages truncate apically and produced laterad, and a phallus with the internal tubule hooked subapically and apically.
Abstract in English:The taxonomy of the species of Metaxia Monterosato, 1884 from Brazil is revised. Previously to this study, only Metaxia excelsa Faber & Moolenbeek, 1991 was known to occur in this country, under its older name Metaxia exilis (C.B. Adams, 1850). The review of a large amount of shells in malacological collections in Brazil revealed the occurrence of three known additional species: Metaxia taeniolata (Dall, 1889); Metaxia rugulosa (C.B. Adams, 1850); Metaxia prompta Rolán & Fernández-Garcés, 2008, all previously reported from the southeast coast of the USA and/or the Caribbean region. Metaxia gongyloskymnus sp. nov., diagnosed by the globose protoconch with continuous axial ribs and microscopic spiral sculpture, is restricted to localities off the Southeastern Brazilian coast.