Search

Scales in gonadal development can be very important in studies with reproductive biology. Considering the inherent difficulties of the species and the absence of studies with reproduction of Deuterodon langei, was made a specific scale of gonadal development, for male and female, based on macroscopic features like size, shape, coloration, degree of vascularization, positioning of gonads and coloration and size of oocytes. Males and females have gonads occupying dorsolateral position in the abdominal cavity and very adhered in the peritoneum. In early stages the gonads have ribbon form while in advanced stages they are wider and have leaf form. The ovaries vary from dark-yellow to brown while the tests are whitened

Estudos sobre a alimentacao de uma determinada especie geralmente resultam em uma contribuicao para o conhecimento da mesma e sao fundamentais para a compreensao do funcionamento do ecossistema do qual esta faz parte. O presente trabalho buscou ampliar o conhecimento sobre a ecologia alimentar de Deuterodon langei Travassos, 1957, por meio de analises sobre a composicao da dieta, partilha de recursos, estrategia alimentar e o papel dos componentes intra- e inter-individuais na amplitude do nicho alimentar da especie, enfocando variacoes entre diferentes classes de comprimento num mesmo intervalo temporal e espacial. A dieta de D. langei foi considerada de um modo geral como onivora, apesar da notavel diminuicao dos itens animais e concomitante aumento da importância de itens de origem vegetal durante o processo ontogenetico. Foi constatada a existencia de diferentes estrategias alimentares e de uma certa partilha de recursos entre as diferentes classes de comprimento. ABSTRACT Studies on feeding behaviour in general contribute significantly for the knowledge about the biology of the species, and are crucial for the understanding functional relations within the ecosystem in which the species is inserted. The present study aimed the knowledge about the feeding ecology of Deuterodon langei Travassos, 1957, through analyses of diet composition, resource partitioning, feeding strategies, and the role of intra- and inter-individual components on the determination of the amplitude of the species´ feeding niche. The study was conducted focusing on variations between different size classes within a same time and space interval. The diet of D. langei was in general considered omnivorous despite the remarkable reduction in animal items and concomitant increase in vegetal items during ontogenesis. Different feeding strategies and a certain degree of resource partitioning between different size classes of this species was thus detected. RESUME Des recherches sur la nourriture concourent pour la connaissance des especes et sont relevants pour la comprehension du fonctionnement de l’ecosysteme. On a determine dans ce travail la composition du regime de nourriture de Deuterodon langei Travassos, 1957, la partage de ressources, la strategie de la nourriture et le role des composantes intra et interindividuales dans l’amplitude du creneau alimentaire de l’espece, en focalisant variations entre des classes differentes de longueur dans un meme intervalle temporal et spatial. Le regime de D. langei est omnivore, malgre la remarquable reduction des itens animaux et augmentation de la role de itens vegetales pendant son developpement ontogenetique. On a ete constatee l’existence de differentes strategies de nourriture et de partage de ressources entre les differentes classes de longueur.