Abstract 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.

RESUMO Das espécies nativas de camarões da América do Sul, Macrobrachium amazonicum (Heller, 1862) é a mais importante para fins de aquicultura, possuindo elevado valor comercial. Devido à sua importância, este estudo objetivou avaliar a plasticidade fenotípica de fêmeas da espécie em relação ao desenvolvimento gonadal, e determinar o tipo de desova. Para tal, foi realizada análise macro e microscópica do aparelho reprodutor. Observaram-se ovários apresentando as seguintes células reprodutivas em sequência de desenvolvimento: oogônias (OO) com diâmetro médio e desvio padrão de 25,4 ± 6,5 µm, oócito pré-vitelogênico (OPV) com 61,7 ± 10,7 µm, oócito vitelogênico (OV) com 113,9 ± 24,5 µm, e oócito maturo (OM) com 308,7 ± 56,3 µm, havendo um aumento do volume devido ao processo de vitelogênese e uma alteração de composição basófila para acidófila. Além destas células, observaram-se células foliculares, oócitos atrésicos e folículos pós-ovulatórios. Unindo análise macro e microscópica, os ovários de M. amazonicum puderam ser classificados em seis estágios: Imaturo, Em maturação, Maturo, Desovado em maturação, Desovado e Repouso. Verificou-se que o desenvolvimento ovariano de M. amazonicum segue um padrão para as diferentes populações. Diante dos resultados encontrados e evidências na literatura, constata-se que a desova para esta espécie é do tipo parcelada ou múltipla, ou seja, sincrônica em mais de dois grupos (lotes de oócitos). Estas observações oferecem uma base para estudos que contribuirão para a criação de medidas de manejo sustentáveis para a manutenção da espécie na natureza, bem como contribuem para elucidar a biologia de seus indivíduos.

ABSTRACT Macrobrachium amazonicum (Heller, 1862) is the most important species for aquaculture native to South America. This study evaluates the phenotypic plasticity of females of Macrobrachium amazonicum with respect to the gonadal development, and determines the spawning type. Our study consisted of macro and microscopic analysis of the reproductive tract. Ovaries exhibited the following reproductive cells in developmental sequence: oogonia (OO) - mean diameter and standard deviation of 25.4 ± 6.5 μm; previtellogenic oocyte (PVO) - 61.7 ± 10.7 μm, vitellogenic oocyte (VO) - 113.9 ± 24.5 μm; and mature oocyte (MO) - 308.7 ± 56.3 μm. Ovaries increased in volume due to vitellogenesis and changing of basophilic to acidophilic composition. Follicular cells, atresic oocytes and postovulatory follicles were also analyzed. By combining macro and microscopic analysis, the ovaries of M. amazonicum were classified into six stages: Immature, In maturation, Mature, Spawned in maturation, Spawned and Resting. The ovarian development of M. amazonicum followed a standard pattern even among different populations. Considering our results and the evidence in literature, we conclude that spawning for this species is parceled or multiple, that is, synchronous in more than two groups (clutches of oocytes). Such observations provide basis for further studies addressing sustainable management strategies for species conservation and contribute to elucidate the biology of their specimens.

Abstract The present study describes the first record of bilaterally hypertrophied chelipeds in a male fiddler crab, Minuca rapax (Smith, 1870), collected in the mangrove area near the city of Jaguaribe, located in the northern portion of Itamaracá Island in Pernambuco, Brazil. This particular specimen was captured by hand as it emerged from its burrow. Of the total 126 individuals (48 females and 78 males) of the genus Minuca (Bott, 1954) captured, only one presented chelipeds similar in size and shape. Some of the causes of malformation in decapods have been attributed to a double generation of growth areas or non-synchronous regenerative coordination in wound healing. Due to the lack of studies on the definitive cause of these abnormalities and deformations, further investigations are required to determine the roles of individuals with abnormalities within populations as well as the principal causes of these abnormalities.

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.

Varios estudios realizados en las islas oceánicas brasileñas han generado resultados de gran importancia para la comprensión de estos ecosistemas. Sin embargo, la mayoría de estos estudios se han limitado a aguas poco profundas, no más allá de 200 m de profundidad. Se analizan siete campañas experimentales de pesca en aguas profundas efectuadas con trampas de fondo en el Archipiélago de San Pedro y San Pablo, a profundidades de 300 a 700 m, entre 2012 y 2014. Durante estos estudios, se registró la presencia de 458 especímenes del cangrejo de profundidad Chaceon gordonae. De los ejemplares analizados, 252 fueron machos y 206 hembras. La longitud de caparazón (CL) midió en promedio 110,81 ± 14,52 mm en los machos y 102,00 ± 16,55 mm en las hembras. En general, el parámetro β1 de la relación longitud-peso mostró un crecimiento alométrico positivo. La comparación de la regresión lineal entre la longitud de caparazón y la longitud y ancho de la chela derecha en los machos indicó una madurez morfológica a 108,90 y 110,10 mm LC, respectivamente, mientras que la regresión entre la longitud y ancho del caparazón del abdomen de las hembras indicó una talla de madurez morfológica a los 84,00 mm CL.

A batimetria de um corpo d'água pode ser medida em campo, a partir de sondas batimétricas; no entanto, é um processo oneroso e que demanda tempo. Com isso, o objetivo principal deste estudo foi ajustar modelos de estimativa de batimetria de um lago a partir de dados orbitais. O trabalho foi realizado no açude do Saco, localizado na bacia hidrográfica do Rio Pajeú, na cidade de Serra Talhada - PE. Foram ajustados modelos de regressão entre os valores batimétricos, coletados com auxílio de uma sonda, as bandas espectrais verde e infravermelho próximo do satélite Landsat 5 TM e o índice da diferença normalizada da água. A avaliação dos modelos ajustados foi realizada pela análise do coeficiente de determinação, do erro quadrado médio e da eficiência do modelo. A batimetria do açude variou entre 0,3 e 10 metros de profundidade. Os melhores ajustes foram encontrados com a utilização dos modelos potencial e exponencial, com valores de coeficiente de determinação superiores a 0,46 e de eficiência do modelo próximos da unidade. Pode-se concluir que os modelos de batimetria, ajustados a partir de dados de sensoriamento remoto, estimaram com satisfatória exatidão os valores de batimetria do açude do Saco, principalmente nas partes mais rasas do lago.

The bathymetry of a water body can be measured in the field using bathymetric probes; however this process is costly and time-consuming. Thus, the main objective of this study was to fit bathymetry estimation models of a lake from satellite data. The study was conducted in the Saco reservoir, located in the Pajeu river basin near the city of Serra Talhada - PE, Brazil. Regression models were adjusted between the bathymetry values collected with a probe, the green and near infrared spectral bands of the Landsat 5 TM satellite and the normalized difference water index. Evaluation of the adjusted models was performed by analysis of the coefficient of determination, mean squared error and model efficiency. The bathymetry of the reservoir varied between 0.3 and 10 meters deep. The best fits were found when using the power and exponential models, with coefficients of determination greater than 0.46 and model efficiency close to one. It can be concluded that the bathymetry models adjusted to the remote sensing data provided a satisfactory accuracy for estimating bathymetry values of the Saco reservoir, especially in the shallow regions of the lake.