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Background. The common pandora, Pagellus erythrinus (Linnaeus, 1758), is widely distributed in the Black and the Mediterranean seas. Therefore, P. erythrinus is a valuable component of the commercial fishery in Tunisia and plays an important role in microeconomics of local areas. The goal of this study was to investigate the stock structure and otolith asymmetry for specimens of the common pandora sampled from two lagoons—Ghar El Melh and Bizerte. Materials and methods. We collected a total of 119 specimens of P. erythrinus from the two lagoons, from May through July 2016. The Elliptical Fourier Analysis (EFA) was determined to evaluate the degree of similarity in the otoliths and detect the reciprocal variability. Results. The Discriminant Factor Analysis for the sagitta shape clearly demonstrated an asymmetry when comparing otoliths (left–right) (P < 0.05) within each population and a difference in shape when comparing the same side between the two populations: between the two sides (right–right and left–left). Conclusion. The comparison of the otolith morphology of the two populations showed a clear difference in shape and a left–right asymmetry of otoliths between and within populations. This result is probably related to genetic and local environmental factors. In fact, this investigation improves the knowledge on the stock discrimination for P. erythrinus and provides useful information for analysing fisheries management of this species in Tunisia.

Background. The thinlip grey mullet, Liza ramada (Risso, 1810), is widespread in Tunisia. Despite its economic importance, the stock discrimination of this fish is poorly understood. The aim of this study is to investigate, for the first time, the stock discrimination of this species for two Tunisian populations based on the otolith shape, using different statistical approaches. Materials and methods. The specimens of L. ramada were collected during three months (from March to May 2013) at two sampling sites: the marine (Cap Zebib sea resort) and the estuarine (Mellegue Dam) in Tunisia. We analysed sagittal otolith shape variation for 120 individuals (60 fish of each study site comprising 30 males and 30 females) for both sexes (males and females) and two sides (left and right otolith) for each specimen. Results. Statistical- and discriminant function analysis of the sagittal otolith shape clearly demonstrated statistically significant differences from the two populations. These results were also confirmed by highly statistically significant difference between otolith shape (left and right) for both sexes. An asymmetry was detected when comparing otoliths of the same side (RR–LL) between different sampling sites. Conclusion. The shape variability of otolith between these two sampling sites is probably correlated with local environmental and ecological factors.

The first records of Lampris guttatus in the Mediterranean Sea date back to 1807. Yet, until now it has been considered as a rare species (less than 25 specimens recorded in the literature). Since 2008, at least 23 specimens have been fished or observed along the French Mediterranean coast. In this paper, we present an updated review of records in the Mediterranean and discuss the possible link with the present sea water warming. We hypothesise that the recent Mediterranean specimens could come from the Atlantic, throughout the Gibraltar Strait, following a northward migration along the Northeast Atlantic coast due to present global warming.