Resumo em Inglês:

Tadpoles of two sympatric anurans, Bufo gargarizans Cantor, 1842 and Rana zhenhaiensis Ye, Fei & Matsui, 1995, were used as model organisms to examine the effects of different levels of tail loss on swimming performance and survival. On average, B. gargarizans tadpoles were shorter and had smaller tails and body mass than R. zhenhaiensis. After 75% tail loss, the survival rate of experimental and control B. gargarizans tadpoles, and of experimental tadpoles of the two species, differed significantly; the number of tadpoles surviving a complete impairment of their swimming ability did not differ between B. gargarizans and R. zhenhaiensis. After 50% tail loss, the swimming performance (swimming speed, maximum distance and number of stops) of the two species was significantly affected. However, the adverse influence of tail loss on the swimming speed of B. gargarizans tadpoles was greater compared to R. zhenhaiensis tadpoles. Our data indicates that a 50% tail loss results in swimming costs for B. gargarizans and R. zhenhaiensis tadpoles, and that 75% tail loss decreases the survival rate of B. gargarizans tadpoles. Therefore, we conclude that tadpoles of different species and with the same degree of tail loss use distinctive strategies to improve individual fitness in the face of predator pressure.

Resumo em Inglês:

Phenanthrene, a Polycyclic Aromatic Hydrocarbon, remains adsorbed to sedimentary particles in aquatic environments. It affects mainly benthic organisms, and is considered potentially genotoxic. In ecotoxicology, species of Chironomus Meigen, 1803 are widely known as bioindicators of the effects of chemicals on aquatic organisms. This study investigates the effects of phenanthrene on the size of the head capsule of Chironomus sancticaroli Strixino & Strixino, 1981 larvae after chronic (eight days) exposure, and DNA damage after acute (96 hours) and chronic exposure (eight days), under laboratory conditions. DNA damage, evaluated using the alkaline comet assay, detected effects for both exposure periods, indicating that phenanthrene is toxic for C. sancticaroli. For the acute exposure, we analyzed five concentrations of phenanthrene, between 0.16 mg.l-1 and 1.60 mg.l-1, detecting significant differences (Kruskall-Wallis test with p < 0.05) in the degree of DNA damage in all groups. These effects were not dose-dependent. For the chronic exposure, two concentrations (0.16 mg.l-1, 0.83 mg.l-1) were analyzed, and DNA damage was observed in both. Again, the effects were not dose-dependent. This indicates that phenanthrene is genotoxic to larvae of C. sancticaroli even at low concentrations. The size of the head capsule was evaluated after chronic exposure to concentrations of 0.16 mg.l-1 and 0.83 mg.l-1. Significant differences (ANOVA test with p < 0.05) were detected in the two concentrations, and a reduction in the size of the larval head capsule was observed. This suggests that phenanthrene causes delay in larval development. These results indicate that phenanthrene affects the development of and causes DNA damage in C. sancticaroli larvae. Therefore, we suggest that C. sancticaroli can be used as a biological indicator for environmental contamination with phenanthrene.

Resumo em Inglês:

Trawl fisheries are associated with catches of swimming crabs, which are an important economic resource for commercial as well for small-scale fisheries. This study evaluated the population biology and distribution of the swimming crab Callinectes ornatus (Ordway, 1863) in the Estuary-Bay of São Vicente, state of São Paulo, Brazil. Crabs were collected from a shrimp fishing boat equipped with a semi-balloon otter-trawl net, on eight transects (four in the estuary and four in the bay) from March 2007 through February 2008. Specimens caught were identified, sexed and measured. Samples of bottom water were collected and the temperature and salinity measured. A total of 618 crabs were captured (332 males, 267 females and 19 ovigerous females), with a sex ratio close to 1:1. A large number of juveniles were captured (77.67%). Crab spatial distributions were positively correlated with salinity (Rs = 0.73, p = 0.0395) and temperature (Rs = 0.71, p = 0.0092). Two peaks of recruitment occurred, in summer and autumn, and ovigerous females were mostly captured during summer, showing a seasonal reproductive pattern. The results showed that C. ornatus uses the bay as a nursery area for juvenile development. Callinectes ornatus is not yet a legally protected species, and the minimum allowed size of crabs caught in the area, although already restricted, should be carefully evaluated since the removal of large numbers of juveniles could negatively impact the local population.

Resumo em Inglês:

Aquatic invertebrate biomass estimations are often important in ecological and biological studies. Biomass may be determined by regression models between body and case dimensions and dry mass. Using linear, exponential and power regressions we analyzed the relationship between body and case dimensions and the biomass of Phylloicus elektoros Prather, 2003. Furthermore, we used cross-validation to evaluate the predictions of our models and of the models developed for Phylloicus sp. from southeastern Brazil. We measured four body dimensions (head capsule width, interocular distance, body and pronotum length) of 152 larvae and two case dimensions (width and length) of 45 cases. Case width provided better fit with biomass than case length in all model classes. Body length provided the best biomass prediction. Biomass predictions using models proposed in the literature were 75% lower than the observed values. The power model provided the best fit between body and case dimensions with biomass. However, exponential models also provided good biomass estimates. We observed a close fit between body and case dimensions and biomass, but the predictive power of the models was low (~40%). The predictive power of models proposed in the literature was much worse than those built from local data and thus we do not recommend their use to predict the biomass of organisms from different regions.

Resumo em Inglês:

We inventoried the birds from Serra do Aracá region, state of Amazonas. The region encompasses a high diversity of vegetation types, including white sand forests and campinas, terra firme and flooded forests, montane forests and tepuis. We recorded 416 bird taxa in 69 families through captures with mist nets, tape recording of bird voices, and collection of voucher specimens. A large proportion of them (61%) were recorded in a single vegetation type. Qualitative estimates suggest that approximately 580 bird species occur in the region. The avifauna of the Aracá region has a mixed biogeographic composition, with species typical of both margins of the Rio Negro occurring sympatrically. Additionally, species whose distributions are restricted to three areas of endemism for Amazonian birds (Imeri, Guiana and Pantepui) were recorded in the region. Rare landscapes in the Brazilian Amazon are found in the Serra do Aracá region. Additionally, we recorded endemic and rare birds, highlighting the value of the region for conservation. The Serra do Aracá State Park officially protects montane forests, terra firme forests and tepuis. We suggest that the large extension of white sand campinas and igapó forests at the southern portion of Serra do Aracá should be also preserved in order to improve the representation of the rich natural heritage of the region.

Resumo em Inglês:

Various studies have focused on the richness and abundance of bats in tropical forests and how the composition of these forests affects bat assemblages, but there are few studies on the relationship of bats with riparian forests. The aim of this study was to ascertain the differences among bat assemblages of three riparian forest areas of the Tinguá region, state of Rio de Janeiro, Brazil. These areas were: I) an agricultural area (Takume); II) a reforested area in primary succession (Canavarro); and III) an area with late secondary vegetation (Tinguá Biological Reserve). Assessments of bat species composition in these areas may shed light on how anthropogenic modifications in riparian forests can influence local bat assemblages. Bats were captured with mist nets during 72 sampling nights. Total bat abundance was 1,511 individuals in 26 species. The three areas differed in their species composition. The Tinguá Biological Reserve was the richest area, Canavarro presented the lowest diversity and the highest abundance of individuals, and the evenness index was highest in Takume. The differences found in the composition and ecological indices indicate that bat assemblages have distinct characteristics in the three areas studied, with varied degrees of transformation and anthropization.

Resumo em Inglês:

Serracutisoma gnaspinii sp. nov. is described from the coastal Ombrophylous Dense Atlantic Rain Forest of Paraná and São Paulo states. It differs from other Serracutisoma by having a retrolateral row of spines on femur IV, a rounded white-mark on the carapace and a low dorsal apophysis on trochanter IV. It is likely the sister-species of S. proximum, and with it and other five species forms the S. proximum group, herein formally proposed. Given that the biologic, phylogenetic and biogeographic aspects of Serracutisoma have been studied, the implications of the discovery of a new species are discussed, for instance the evolution of male fight, aggregation and maternal care, traits that are shared with other species. The geographic range of Serracutisoma gnaspinii sp. nov. is compatible with the "Paraná" area of endemism, but with an unique distribution pattern compared to other endemic harvestmen species, which could indicate a new area of endemism also occupied by the primate Leontopithecus caissara Lorini & Persson, 1990.

Resumo em Inglês:

Mimon koepckeae Gardner & Patton, 1972 is a poorly-known bat species, with only three known specimens, including the holotype. Its distribution is restricted to the type locality in Ayacucho Department, Peru, and surroundings. This species has been synonymized with M. crenulatum by some authors. Based on a new specimen of M. koepckeae collected from Santuario Nacional Pampa Hermosa, Junin Department, Peru, we provide an extensive morphological comparison with M. crenulatum (Geoffroy St.-Hilaire, 1803), Mimom bennettii (Gray, 1838), and Mimon cozumelae Goldman, 1914, concluding that M. koepckeae is a valid species. As a result the distribution range of the species is extended 160 km north of the type locality. In addition, we characterize the habitat of the species, provide current data on feeding behavior, and suggest that M. koepckeae should be categorized as endangered species.

Resumo em Inglês:

Syntypes of Tettigonia vermiculata Signoret, 1855 were studied and redescribed, including the first description and illustration of the male and female genitalia of this species. Based on this study, this Brazilian species, previously placed in Molomea (Proconiini), is herein transferred to Versigonalia (Cicadellini). This transfer resulted in a secondary homonymy and its junior homonym from Argentina, Versigonalia vermiculata Young, 1977 is considered invalid. Thus, we propose a new name, V. lentiginosa nom. nov., for the latter. A taxonomic key to all three species of Versigonalia is also given.

Resumo em Inglês:

Based on preserved specimens from the states of São Paulo and Rio de Janeiro, Flectonotus ulei Miranda-Ribeiro, 1926 is resurrected from its synonymy with Flectonotus fissilis (Miranda-Ribeiro, 1920) and is redescribed. Analysis of osteological characters and brood pouch structure confirms that F. ulei belongs to Fritziana. The species is small for the genus (snout-vent length in males, 19.2-26.9 mm, n = 2; in females, 20.3-21 mm, n = 4) and was found in bromeliads. Flectonotus ulei is characterized by dorsal pattern consisting of interorbital pentagon or hexagon-shaped mark delimited by heavy dark line, diameter of tympanum smaller than that of disc of third digit, and a brood pouch covering the eggs dorsally except for a narrow longitudinal slit; eggs arranged in rosette.

Resumo em Inglês:

A new species of Helochares Mulsant, 1844 (Hydrophilidae: Acidocerinae) from Brazil is described and illustrated. Helochares (s. str.) atlanticus sp. nov. is distinct mainly by characteristics of the aedeagus whose phalobase is short, narrowed on basal third; parameres are thick, constricted on apical quarter, with small tooth-like projection on outer margin near apex; dorsal lobe longer than ventral lobe, shorter than parameres, very wide at base, abruptly narrowing toward apex until about half of its length where it dilates and divides into two long and narrow projections apart from each other at base, but turned inward at apex; ventral lobe acuminate and symmetrical. The rounded emargination on anteromedial margin of labrum bearing small tooth-like projections and the convex and slightly elevated mesoventral process, without high-elevated carina, also helps in identifying the species. Specimens of the new species were collected in the mountain region of the state of Rio de Janeiro (municipality of Teresópolis) and in the north coast of the state of São Paulo (municipality of Ubatuba), both localities in Southeastern Brazil. Helochares (s. str.) oculatus Sharp, 1882 and Helochares (Sindolus) femoratus (Brullé, 1841) are recorded for the first time from the state of Rio de Janeiro.

Resumo em Inglês:

Hersiliidae is a relatively small spider family that is easily distinguished by the very long posterior lateral spinnerets. It is distributed worldwide and, although quite diverse in other zoogeographical regions, is represented by only 11 species in the Neotropics. Hersiliidae was recently revised and of the 11 species, three are known solely from one sex. Yabisi Rheims & Brescovit, 2004 includes only two species, one of which is known solely from the female. The genus is extremely rare and both species are known from only a few specimens. In this paper, the male of Yabisi guaba Rheims & Brescovit, 2004 is described and illustrated and an extended diagnosis is given for the genus. The male of this species is distinguished from its congener by the palps, with laminar embolus having the same width throughout its length and median apophysis narrow and distally rounded.

Resumo em Inglês:

Parasitism by horsehair worms (Nematomorpha) in Mantodea is well known, but only a few cases of intersexuality were reported in the literature. In the present study, intersexuality of the holotype of Photina gracilis Giglio-Tos, 1915 is documented as a possible consequence of nematomorph parasitism. Photina gracilis and Photina laevis Giglio-Tos, 1915 are established as new subjective junior synonyms of Photina vitrea (Burmeister, 1838). The female holotype of Mantis (Cardioptera) gymnopyga Burmeister, 1838, which was associated and synonymized with P. vitrea, is recognized as a member of the genus Coptopteryx and the combination Coptopteryx gymnopyga (Burmeister, 1838) is revalidated. The substitute name Photina gymnopyga (Burmeister, 1838), instead of Mantis (Photina) vitrea Burmeister, 1838 (nec Mantis vitrea Stoll, 1813), is discarded and established as a new synonym of Coptopteryx gymnopyga. The name vitrea Burmeister, 1838 must be maintained until ruling by the International Commission on Zoological Nomenclature.