Geometric morphometrics and morpho-anatomy: a combined tool in the study of sea bream (Sparus aurata, sparidae) shape

The effects of different conditions of larval and postlarval rearing on the external morphology and morpho-anatomical characters were studied on adult specimens of Sparus aurata L. (Teleostea, Sparidae) after 15 months of common rearing in floating cages. Differences in external morphology between two samples were analysed with geometric morphometrics. Despite common rearing, significant differences in shape were found, evidence of the importance of larval and postlarval rearing conditions in determining shape features. On the same specimens, morpho-anatomical data were collected using X-rays, thus making it possible to correlate fish shape with morpho-anatomical data. Characteristic shapes were associated with particular cadres of morpho-anatomical anomalies, such as lordosis of different body regions and the bending of the same. Streamlined wild-like profiles were associated with light anomaly cadres. Fish shape is an important component affecting the market value of the species. The use of the combined approach proposed is thus recommended in the description and quantification of shape features, particularly in the context of fish quality assessment.