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The embryonic development of four species of the family Palaemonidae was studied under laboratory conditions. Adults of Macrobrachium olfersi (Wiegman, 1836), Macrobrachium potiuna (Müller, 1880), Palaemon pandaliformis (Stimpson, 1871) and Palaemonetes argentinus (Nobili, 1901) were collected in Santa Catarina Island, Santa Catarina, Brazil and maintained at 26ºC. The following embryonic characters were analyzed: egg shape, yolk organization and cleavage plane, naupliar and post-naupliar appendages, stomodeum, optical lobes, eyes, telson, embryo curvature and the space occupied by the embryo in the egg. Different rates of development were observed for the four species, with M. potiuna showing the longest time of embryogenesis. The species studied followed the pattern of embryogenesis of centrolecithal eggs, enabling the identification of similar features of the development, and the establishment of eight common embryonic stages.

ABSTRACT. Reproductive biology of Macrobrachium o({ersii (Wiegman) (Crustacea, Decapoda, Palaemonidae) collected at Santa Catarina's lsland, Brazil. The aim of this study is to characterize the reproductive features of Macrobrachium olfersii (Wiegman, 1836) from Santa Catarina' s Island. The animaIs were collected in freshwater streams ofthe Ratones Hidrografic Basin (site A I) and at the Peri's Pond (site A2). In the laboratmy, the procedures of sexual differentiation were canied out to c1assify the individuaIs in males, females or ovigerous females, followed by the detennination oftotal weight (g), quelipod relative weight (g) and totallength (mm). The eggs were removed from the ovigerous females and counled. Sexual malurity and fecundity were analyzed based in the dimensions and number of eggs carried by ovigerous females. The water temperature on lhe capture sites varied from 17 to 29°C throughout lhe months of study. A total of 503 individuaIs were captured, wilh 129 individuaIs from site A I and 374 ll'om site A2 . The mean total size and lenglh was 49.65 mm and 3.79 g for lhe males, 38.75 mm and 1.61 g for lhe females and 36.19 mm and 1.08 g for the ovigerous females. At the sites A I and A2, the individual sexual maturity was reached with 27.3 and 21.2 mm of total length, respectively, while populational sexual maturity was estimated for the 45.0 to 50.0 mm c1ass at site AI and for the 30.0 to 35.0 mm class at site A2. The ovigerous females carried an average of 3464 eggs at site A I, and 1440 eggs at site A2. These reproduclive feature s, presented by M olfersii, show the species' plasticity, which can be associated with environmental variations, contributing to ils reproductive success. KEY WORDS. Macrobrachium olf ersii, fecundity, sexual maturity, environmental condilions Na Ilha de Santa Catarina foram registrados representantes da família Palaemonidae (Rafinesque, 1815), identificadas como Macrobrachium acanthurus

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Glyphosate (N-phosphonomethyl-glycine) (GLY) is the active ingredient of the most used herbicides in the world. GLY is applied in formulated products known as glyphosate-based herbicides (GBH), which could induce effects that are not predicted by toxicity assays with pure GLY. This herbicide is classified as organophosphorus compound, which is known to induce neurotoxic effects. Although this compound is classified as non-neurotoxic by regulatory agencies, acute exposure to GBH causes neurological symptoms in humans. However, there is no consensus in relation to neurotoxic effects of GBH. Thus, the aim of this study was to investigate the neurotoxic effects of the GBH in the zebrafish Danio rerio, focusing on acute toxicity, the activity and transcript levels of mitochondrial respiratory chain complexes, mitochondrial membrane potential, reactive species (RS) formation, and behavioral repertoire. Adult zebrafish were exposed in vivo to three concentrations of GBH Scout, which contained GLY in formulation (fGLY) (0.065, 1.0 and 10.0 mg L fGLY) for 7 d, and an in vitro assay was performed using also pure GLY. Our results show that GBH induced in zebrafish brain a decrease in cell viability, inhibited mitochondrial complex enzymatic activity, modulated gene expression related to mitochondrial complexes, induced an increase in RS production, promoted hyperpolarization of mitochondrial membrane, and induced behavioral impairments. Together, our data contributes to the knowledge of the neurotoxic effects of GBH. Mitochondrial dysfunction has been recognized as a relevant cellular response that should not be disregarded. Moreover, this study pointed to the mitochondria as an important target of GBH.

Glyphosate is a broad-spectrum organophosphate (OP) herbicide, highly soluble in water, and when applied in terrestrial systems it penetrates into soil, eventually reaching the aquatic community and affecting nontarget organisms. The aim of this study was to evaluate the toxicity of glyphosate on ovaries of zebrafish (Danio rerio). Ovaries (n = 18 per triplicate) were exposed to 65 μg/L of glyphosate [N-(phosphonomethyl) glycine] for 15 d. This concentration was determined according to Resolution 357/2005/CONAMA/Brazil, which establishes the permissible concentration of glyphosate in Brazilian inland waters. Nonexposed ovaries (n = 18 per triplicate) were used as control. Subsequently, morphology and expression of steroidogenic factor-1 (SF-1) of exposed and nonexposed ovaries was determined. No apparent changes were noted in general morphology of exposed and nonexposed ovaries. However, a significant increase in diameter of oocytes was observed after exposure to glyphosate. When ovarian ultrastructure was examined the presence of concentric membranes, appearing as myelin-like structures, associated with the external membranes of mitochondria and with yolk granules was found. After glyphosate exposure, immunohistochemistry and immunoblotting revealed greater expression of SF-1 in the oocytes, which suggests a relationship between oocyte growth and SF-1 expression. These subtle adverse effects of glyphosate on oocytes raised a potential concern for fish reproduction. These results contribute to understanding glyphosate-induced toxicity to nontarget organisms, showing subcellular and molecular impairments that may affect reproduction in +female fish.

Sepsis induces increased expression and physical association of nitric oxide synthase 1/soluble guanylate cyclase and a higher production of cyclic guanosine monophosphate that together may help explain sepsis-induced vascular dysfunction. In addition, selective inhibition of nitric oxide synthase 1 restores the responsiveness to vasoconstrictors. Therefore, inhibition of nitric oxide synthase 1 (and possibly soluble guanylate cyclase) may represent a valuable alternative to restore the effectiveness of vasopressor agents during late sepsis.

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