Universität Rostock, 2008
Abstract: Sixteen Lessepsian fish species, representing 14 families, have been found recently in Libya. Ca. 50% of them were found all along the Libyan coast, 12.5% in the east and central regions, and 37.5% were restricted to the eastern part. All occur in the coastal area (1-50 m depth). More than 37% are of commercial value, especially Rabbitfish (Siganus spp.), which was studied intensely. Siganus luridus and S. rivulatus differ in niche characteristics as spawning time (S. luridus covered three months May-July and only two months June and July for S. rivulatus. Regarding food and feeding, Phaeophyceae and Chlorophyceae are more frequent for S. luridus, whereas for S. rivulatus the most frequent food category was Chlorophyceae. The age and growth were studied. Genetically, the results indicated high haplotypes diversity (Hd) and low nucleotide diversity (π), in all populations. The neighbour-joining and network analysis based on two genes revealed no significant phylogeographic structure for both species. These results suggest that both Siganus spp. belong to the same gene pool. Two native Mediterranean cymothoid species caught attached to the first record on Siganus spp.
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