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Relationships between phenological and morphophysiological traits of functional groups of woody species in riparian forests of semi-arid environments are little understood, especially regarding the representativeness of these groups in the community. This study aimed to evaluate the influence of the leaf and wood morphofunctional characteristics on the vegetative phenology of woody species in a riparian forest in the Brazilian semi-arid region and how these traits act in the distribution of species in functional groups. Vegetative phenology and leaf traits (specific leaf area, leaf area, leaf thickness, and leaf dry matter content), wood density, and amount of saturated water in the stem and their association with soil water availability, relative air humidity, precipitation, temperature, photoperiod, and vapor pressure deficit were evaluated. Cluster analysis showed three functional groups (n = 23): deciduous low wood density species (9%), deciduous high wood density species (48%), and non-deciduous species, which included semideciduous (17%) and evergreen species (26%). Deciduousness was positively related to specific leaf area and negatively related to leaf dry matter and leaf area. Deciduous and semideciduous species (55.1% and 7.5% of the individuals in the community, respectively) showed a strong dependence on abiotic factors linked to precipitation and temperature, while the evergreen species showed a strong dependence on the vapor pressure deficit to trigger their phenophases. We concluded that the studied functional traits act on the leaf habit, which is essential to understand how the phenology is projected within functional groups. [ABSTRACT FROM AUTHOR]

We describe the development and maturation of the germ cells of the brachyuran crab Eriphia gonagra (Fabricius, 1781). Monthly collections were conducted in Pernambuco state, northeastern Brazil, from November 2018 to October 2019 during the low spring tide. The anatomy of the reproductive system of female individuals follows the basic brachyuran pattern. Five cell developmental stages were identified based on the morphological changes in the developmental stages: oogonia (7.10 ± 1.85 µm), pre-vitellogenic oocytes (42.23 ± 8.61 µm), oocytes in initial vitellogenesis (130.49 ± 21.93 µm), vitellogenic oocytes (139.68 ± 23.45 µm), and mature oocytes (214.77 ± 90.81 µm). Developmental stages were defined and related to gonad coloration and germ- cell development; five maturational stages were identified: immature, initial maturation, advanced maturation, mature, and spawning/resting. [ABSTRACT FROM AUTHOR]

We analyzed aspects related to the relative growth and reproduction of females of Macrobrachium amazonicum (Heller, 1862) in a population of the semiarid Northeast Region of Brazil. Carapace (CL) and total length (TL) ranged 5.57–17.61 mm (mean 10.96 ± 2.07 mm) and 28.96–80.63 mm (mean 52.14 ± 9.13 mm), respectively. Relative growth analysis showed that total length increased in a higher proportion than carapace region (positive allometry). This region also increased in a higher proportion regarding weight (negative allometry) due to energy cost in reproduction. Of the three criteria used to determine size at the onset of maturity (SOM), the smallest size observed was obtained by physiological SOM I (based on advanced vitellogenesis): 8.22 mm CL, followed by functional SOM II (8.83 mm CL, based on ovigerous females) and physiological SOM III (9.48 mm, based on CL50). SOM was influenced by the population's phenotype, and SOM I and SOM II showed synchronicity. The estimated maximum fecundity was 2,805 eggs per female, with a mean value of 690 eggs. There was continuous reproduction and the dry season favored the percentage occurrence of ovigerous females (September-December 2016 and July-August 2017). The smaller lengths of the individuals, compared to other female populations, were due to the characteristics of the environment and the intrinsic traits of the studied population. The negative allometry for the length-weight relation and the continuous reproductive period with seasonal variation was similar as that recorded for other Brazilian localities. This suggests that these last characteristics are a pattern for this species, which shows a latitudinal variation only in the sizes reached. The fast maturation and continuous reproduction of M. amazonicum females make them a potential species for commercial exploitation. [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]

Some 2178 male and 2109 female Callinectes danae Smith, 1869 were caught in Northeastern Brazil, from March 2009 through February 2010; we reared 24 males and 24 females for 6 months. The relative growth (relation between weight and cephalothorax width) showed negative allometry, except in adult males. The females presented marked changes in relative size of the fifth pleomere as they matured, while the males showed changes in chela size. As rearing progressed, the females underwent ecdysis five times while the males underwent ecdysis six times. The puberal molt was the last to occur. The von Bertalanffy growth model (with to) provided the best fit, when compared to the von Bertalanffy (with CW0), von Bertalanffy (with t0 = 0), Gompertz, and Richard models. The following growth functions for reared individuals were obtained: CWt = 9.88(1-exp(-0.0228(t+14.27))) and CWt = 8.02(1 -exp(-0.0158(t+26.23))). For wild individuals the growth functions were as follows: CWt = 12.12(1 - exp(-0.0052(t + 29.36))) and CWt = 9.48(1 - exp(-0.0036(t + 59.04))), for males and females, respectively. The individuals reached smaller sizes in the rearing system; however, the growth rate was higher. The mean longevity ranged from 375 to 429 days for males and from 458 to 553 for females. The maximum longevity ranged from 550 to 860 and from 764 to 1205 days, for males and females, respectively. [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]

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]

In order to know the morphological variations of Goyazana castelnaui, we conducted an ontogenetic study from the first crab stage to the adult stage using geometric morphometry. We studied 36 females, 43 males and 162 juveniles collected in the Pajeú River, Brazil. We photographed crabs' carapace, pleon and right cheliped with they arranged parallel to the plane, afterwards landmarks and semi-landmarks were strategically distributed in the images. Through principal components analysis, we observed that the variation occurred mainly in the frontal and posterior region of the carapace. The pleon presented marked variations in the posterior and anterolateral region, while chelipeds presented greater variations at the base of the fixed finger. The canonical variation between sexes and between juveniles and adults (p<0.05) varied significantly. Correct allocations obtained by discriminant analysis (p<0.05) varied between 89.3% and 100.0%. The carapace shows a constant dimorphism along the ontogenetic trajectory, and both sexes reach similar centroid sizes (p>0.05). While the pleon and the cheliped, both sexes are similar when juvenile, diverging along the trajectory and reaching different centroid sizes (p<0.05). Females have a larger pleon and males a larger cheliped, corroborating the monophyletic theory of Brachyura.