New protocol to affix sample for environmental and high vacuum electron microscopy.

Electron microscopy has become increasingly essential as an investigative research resource in various fields of science. Despite the evolution of the equipment and preparation techniques, little has been published on techniques for affixation and removal of samples on the stubs after analysis. This work aims to illustrate a quick and low-cost procedure for fixing and removing a sample from the support for analysis by electronic microscopy, applied to crustacean and insect species, as well as other invertebrates.

Three new records of Cladocera (Crustacea: Branchiopoda) for the State of Maranhão, Northeastern Brazil.

Brazilian biodiversity is still poorly studied, especially in the northeast region of Brazil. In the state of Maranhão, the rich fauna is still under-explored in relation to the Cladocera, and this geographic area covers four biomes, which makes it an important field of research on the Cladocera community. In this work, the record of three species is reported: Dadaya macrops Sars, 1901 first record of the genus for the state, Simocephalus serrulatus (Koch, 1841) and Simocephalus latirostris (Stingelin, 1906).

Monogamy in the Burrowing Shrimp Rodrigues & Shimizu, 1992 (Decapoda, Gebiidea, Axianassidae).

Our knowledge of the mating systems in burrowing shrimps (infraorders Axiidea and Gebiidea) is still rather limited. Here we describe the burrow use pattern, sex ratio, and sexual dimorphism of the burrowing shrimp to test for monogamy, considering that monogamous species live in heterosexual pairs and exhibit a low degree of sexual dimorphism. To this end, a total of 226 individuals of were collected from the northeast region of Brazil.

Richness and composition of the Cladocera community (Crustacea: Branchiopoda) from the Maranho State, Northeast Brazil.

The state of Maranho, northeast Brazil, has four different biomes. The water bodies in Maranho belongs to three hydrographic regions. Thus, the state potentially contributes to a high biodiversity.

New records of Anthalona acuta Van Damme, Sinev & Dumont 2011 and Anthalona brandorffi (Sinev & Hollwedel, 2002) in Brazil, with description of a new species of the simplex-branch (Crustacea: Cladocera: Chydoridae).

The range of geographical distribution of Anthalona acuta Van Damme, Sinev & Dumont 2011 and Anthalona brandorffi (Sinev & Hollwedel, 2002) in Brazil has increased by almost 2000 km to the south. New records of Anthalona verrucosa verrucosa (Sars, 1901) were also added. Populations of Anthalona brandorffi from Central Brazil showed a peculiar morphological variation, with some individuals having only a single denticle on the labral keel.

A Survey of Escherichia coli and Salmonella in the Hyporheic Zone of a Subtropical Stream: Their Bacteriological, Physicochemical and Environmental Relationships.

The Hyporheic Zone is among the most important interstitial freshwater habitats, but the relationship between biotic and abiotic factors in this zone remains under-explored. Enterobacteria were expected to be present, but no specific studies had ever confirmed this prediction. The aim of this study was, therefore, to evaluate the total coliforms, Escherichia coli and Salmonella spp.

Assessing the ecological condition of streams in a southeastern Brazilian basin using a probabilistic monitoring design.

Prompt assessment and management actions are required if we are to reduce the current rapid loss of habitat and biodiversity worldwide. Statistically valid quantification of the biota and habitat condition in water bodies are prerequisites for rigorous assessment of aquatic biodiversity and habitat. We assessed the ecological condition of streams in a southeastern Brazilian basin.

Determining subsampling effort for the development of a rapid bioassessment protocol using benthic macroinvertebrates in streams of Southeastern Brazil.

The purpose of this study was to establish a subsampling procedure for benthic macroinvertebrates to aid in the development of a multimetric index to assess the biological condition of streams. Data from six streams that are considered minimally impaired were used. Subsampling was done using a device divided into 24 quadrats.

[Use of bioindicators for assessing and monitoring pesticides contamination in streams and rivers].

The objective of this article is to present an analysis of the main bioindicators that are currently used to assess the environmental impact of pollution in water resources. The simple quantification of chemicals in the environment is not enough to reveal the real effects of contamination on ecosystems, making necessary the assessment of the biological effects that pollution causes at different hierarchical levels. The bioindicators used in this article on two case studies comprehend different hierarchical levels: in case study 1, three organization levels were utilized: individual, cellular and molecular, to detect the early effects of exposition to environmental pollutants in three hydrographic basins.