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Abstract: The aim of this study was to characterize the morphology and function of each section of the reproductive system of male Callinectes danae, as well as the stages of reproductive development and their relation to secondary sexual characteristics. Development of their reproductive system begins after completion of the pubertal moult. The growth of the gonopodium showed negative allometry for both juveniles and adults. The reproductive system is divided into portions with different functions. There is a germinal zone in the testes containing spermatogonia, a zone of maturation containing spermatocytes, spermatids or spermatozoa, as well as a collecting duct, which carries spermatozoa to the vas deferens. There are two matrices in the anterior vas deferens that initiate the separation of spermatozoa groups, one composed of polysaccharide acids (matrix I) and another consisting of neutral polysaccharides (matrix II). In the median vas deferens, the matrix II forms an acellular capsule, which forms the spermatophores. In the posterior vas deferens, the matrices are accumulated, initially with a granular texture and are homogenous for the final portion. The ejaculatory duct and penis have muscle lining to expel the spermatophores at copulation. Even after copulation, males retain a stock of spermatophores, allowing copulation with other females. [ABSTRACT FROM AUTHOR]

The abiotic factors are important tools to understand the characteristics of water bodies. Data were analyzed quarterly, from December 2010 to September 2011, around noon, from the top to the bottom of the dam, with three repetitions. The abiotic factors varied slightly with depth. Water temperature, salinity, pH, dissolved oxygen, conductivity and total dissolved solids varied with season. The best cultivation conditions were related to the dry season. The dam showed conditions for the cultivation of Nile tilapia (Oreochromis niloticus) and tambaqui (Colossoma macropomum), and the possibility of cultivating common carp (Cyprinus carpio) and Pacific White shrimp (Litopenaeus vannamei) in ponds with water from the reservoir. [ABSTRACT FROM AUTHOR]

Shinozaki-Mendes, R.A., Silva, J.R.F. and Hazin, F.H.V. 2011. Development of male reproductive system of the blue land crab Cardisoma guanhumi Latreille, 1828 (Decapoda: Gecarcinidae). - Acta Zoologica (Stockholm) 93: 390-399. In this study, the reproductive tract of the Cardisoma guanhumi was described both macroscopically and microscopically. The maturation stages of the reproductive system were defined, and the development of germ cells was described. The reproductive tract is made up of a pair of testis, a pair of vas deferentia, and a pair of ejaculatory ducts. The germ cells were classified in the order of development as spermatogonia (diameter: 10.5 ± 0.11 μm), spermatocytes (9.7 ± 0.07 μm), spermatids (initial phase: 5.5 ± 0.06 μm; final phase: 4.3 ± 0.05), and spermatozoa (SPZ) (4.0 ± 0.03 μm). The testis is made up of a germ zone, a maturation zone and collector ducts, which lead to the anterior vas deferens (AVD), containing solely SPZ. The spermatophores (SPH) start to be formed in the AVD, through the secretion of spermatophoric and protein matrices. In the median vas deferens, the SPH, already fully formed, are stored, while in the posterior vas deferens, a large production of a glycoprotein matrix is observed. Based on macroscopic and microscopic description of the male reproductive tract, three maturation stages are proposed: immature, maturing, and mature. [ABSTRACT FROM AUTHOR]

Swimming crabs (family Portunidae) were collected in Santa Cruz Canal, Brazil from March 2009 through February 2010 using a beach seine and fishing line. The purpose of this study was to characterize the abundance of portunid crab species and to analyse the influence of environmental factors on the catches per unit effort (CPUE) values of Callinectes danae Smith, 1869 in the canal. The catches included five species: C. danae (the most abundant species), Callinectes marginatus (A. Milne-Edwards, 1861), Callinectes exasperatus (Gerstaecker, 1856), Charybdis hellerii (A. Milne-Edwards, 1867) and Callinectes bocourti A. Milne-Edwards, 1879. The species could be assigned to groups according to their abundance and the values of catches were higher during the dry period. The influences of water temperature, tide height, lunar illumination, salinity, precipitation and season were tested, although the average CPUE (μ) of C. danae for the beach seine and line methods was influenced only by tide height (T) and by salinity (S), according to the model: μseine = exp(3.4921 - 1.3584T) and μline = exp(0.055589S). Within the ranges of the environmental variables included in the study, a tide height of 0.1 m was found to optimize the CPUE of the beach seine (28.68 md/h per m²). Furthermore, the CPUE using the line was optimized as the salinity level increased, with a capture rate of 05.92 md/h. [ABSTRACT FROM AUTHOR]

The reproductive pattern of Goyazana castelnaui is described based on the variation of gonadal maturation stages and secondary sexual characteristics. We analyzed 89 specimens from the Pajeú River in the semiarid region of Brazil from September 2014 to August 2015. The average sex ratio was 1F: 0.5M. The carapace width (CW) and weight of females ranged from 1.18 to 4.97 cm and 1.76 to 37.46 g. Male carapace width and weight were between 1.05 and 4.34 cm and 1.11 to 39.71 g. Goyazana castelnaui had a seasonal reproductive cycle that was more active between September and December. Gonad maturation was before the pubertal moult. The spawning season began in August when temperature increased, and ended in February. The onset of the rainy season (November) is thought to be the trigger for a decline in spawning. The gonads of females and males became mature at the same CW50 (2.84 cm). This size is smaller than the morphometric maturation size: 3.85 cm CW in females and 3.65 cm CW in males. This first contribution to the reproductive biology of G. castelnaui should be a basis for further research on its reproduction, especially in other areas of its distribution. Abbreviations: AM: adult male; AF: adult female; °C: Celsius degree; cm: centimeters; Cw: carapace width; CNPq: Brazilian National Council for Scientific and Technological Development; F: female; FC: folicular cells; g: grams; h: hour; INPE: National Institute of Space Research; JF: juvenile female; JM: juvenile male; M: male; MO: mature oocytes; mm: millimeters; µm: micrometer; OO: oogonia; PCA: Principal Component Analysis; PE: Pernambuco; PRPPG: Pro-Rectory of Research and Post-Graduate; PSW: pleon segment width; PVO: pre-vitellogenic oocytes; PVD: posterior vas deferens; RCL: right chela length; RC: ruptured cells; SM: spermatophoric matrix; SP: Spermatophores S: south; Tw: Total weight; UFRPE: Federal Rural University of Pernambuco; VO: vitelogenic oocytes; W: west; [ABSTRACT FROM AUTHOR]

Several studies conducted in Brazilian oceanic islands have generated many results of great significance for the understanding of these ecosystems. However, most of these studies have been restricted to shallow waters, not going beyond 200 m depth. In this work, seven exploratory deep-water fishing surveys were carried out with bottom traps at Saint Peter and Saint Paul Archipelago, between 2012 and 2014, at depths ranging from 300 to 700 m. During these surveys the presence of a deep-sea crab, identified as Chaceon gordonae was recorded, with 458 specimens being caught. Of the sampled specimens, 252 were males and 206 were females. The carapace length (CL) of sampled crabs measured, on the average, 110.81 ± 14.52 mm for males and 102.00 ± 16.55 mm for females. In general, the β1 parameter of the length-weight relationship indicates a positive allometric growth. A comparison of linear regression between the carapace length and right chela length and width for males suggested a morphological maturity of 108.90 and 110.10 mm CL, respectively, whereas the regression between carapace length and abdomen width in females indicated a size at morphological maturity of 84.00 mm CL. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of stocking density on Litopenaeus vannamei at the nursery phase in low-salinity biofloc system. Post-larvae of L. vannmei were cultured for 28 days at 2000, 4000 and 6000 shrimp m-3, and the water quality, plankton composition and growth performance were evaluated. The water quality variables remained within the ideal range for the shrimp culture, and only total suspended solids showed a significant difference between treatments -- the highest stocking density has increased the levels of total suspended solids. In regarding to zooplankton structure, the Protozoa group had the greatest diversity regardless of treatment, and also the greatest abundance (> 66%). For phytoplankton structure, Bacillariophyta (Navicula sp. and Cyclotella sp.) was the dominant class in phytoplankton structure throughout the culture, although a Cyanobacteria bloom has reported at the end of the cultivation at 2000 shrimp m-3. At the end of cultivation, the shrimp yield (0.133 ± 0.028 kg m-3) was significantly higher in the 6,000 shrimp m-3. In contrast, the shrimp survival was significantly higher in the lowest stocking density (71.66 ± 10.36%). Our findings suggest that a density of 6,000 shrimp m-3 should be used under these conditions, but an economic feasibility study should be considered in the future. [ABSTRACT FROM AUTHOR]