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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 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]