Diet of Moenkhausia bonita (Benine, Castro & Sabino 2004) (Characiformes: Characidae) in streams in the basin of rio Formoso, Brazilian Midwest

Abstract

To characterize the diet composition of Moenkhausia bonita and its temporal and ontogenetic variations in streams in the Formoso River basin (MS). The collections were carried out in seven sampling points in two periods throughout the year (dry and rainy). The food items were analyzed according to the volumetric and occurrence frequency methods and the diet was characterized through the Food Index (IAi%). To determine ontogeny, the specimens were divided into five size classes in the dry (D1 to D5) and rainy (R1 to R5) periods. To verify the difference between the species’ diet between the size classes and the periods of the year, the Permutational Multivariate Analysis of Variance – PERMANOVA analysis was performed. Moenkhausia bonita was classified as an invertivore when it consumed basically both aquatic and terrestrial invertebrates (99.5% of the diet), with higher consumption of aquatic invertebrates. There was a significant difference in the diet of between the dry and rainy periods, and although the species basically consumed the same items in the two studied periods, the proportions were different and there was no difference in the diet between size classes. M. bonita diet is based on autochthonous resources regardless of the size class, but that there were different consumption patterns when comparing the different periods of the year. The present study provided the first information on the feeding of M. bonita in a lotic environment and diet spectrum in the developmental phases, (ontogeny) and periods of the year, enabling a better understanding of the species, the importance of invertebrates in its diet, and the need for future studies on the biology, autoecology, and behavior of this species.