Restriction fragment length analysis of the cytochrome b gene and muscle fatty acid composition differentiate the cryptic flatfish species Solea solea and Solea aegyptiaca.

Overlapping external morphometric characters easily confound the flatfishes Solea aegyptiaca and Solea solea (Soleidae) in areas of the Mediterranean Sea where both species live in sympatry. This leads to uncertainties in the fisheries and marketing of the species, in addition to misinterpretations in biogeography and conservation studies. This paper describes a simple restriction fragment length-based diagnostic test that differentiates S.