Caracterização dos otólitos sagitta de espécies capturadas em águas profundas no arquipélago de São Pedro e São Paulo (ASPSP)

Abstract

The otoliths are calcium carbonate structures located in the inner ear of fish, are considered as files that hold valuable information on the biology of fish. Each fish has three pairs of otolithslapillus, sagitta and asteristicus that have microstructure, size, shape and specific functions. The sagitta stands out, being easier to be located and having specific form and functions from species to species. The studies applied to the form of otoliths are research tools in the analysis of stomach contents, identification of stocks and population dynamics. Few scientific works were developed in order to know the ichthyofauna of deep waters in the archipelago of São Pedro and São Paulo (ASPSP). In this work, we used the image processing of the photos of the otoliths of the species captured in the ASPSP, in addition to the Fourier analysis to morphologically describe their aspects and thus characterize the otoliths sagitta of Polimoxia nobilis, Pontinus nigrpunctatus andPhysiculus sp. From the morphometric analysis, a comparison was made between the right and left side and the sex relating to the lengths of the otolith of P. nigropunctatususing Student's t-test and to describe the changes throughout life regressions were made between the measurements and the total length of the individual. The results showed changes in the sagitta otoliths of P. nigropunctatusrelated to the growth of the individual. These results were presented and discussed according to the applied methodology.