Preliminary study on mitochondrial 16S rRNA gene sequences and phylogeny of flatfishes (Pleuronectiformes)

Abstract

A 605 bp section of mitochondrial 16S rRNA gene fromParalichthys olivaceus, Pseudorhombus cinnamomeus, Psetta maxima andKareius bicoloratus, which represent 3 families of Order Pleuronectiformes was amplified by PCR and sequenced to show the molecular systematics of Pleuronectiformes for comparison with related gene sequences of other 6 flatfish downloaded from GenBank. Phylogenetic analysis based on genetic distance from related gene sequences of 10 flatfish showed that this method was ideal to explore the relationship between species, genera and families. Phylogenetic trees set-up is based on neighbor-joining, maximum parsimony and maximum likelihood methods that accords to the general rule of Pleuronectiformes evolution. But they also resulted in some confusion. Unlike data from morphological characters,P. olivaceus clustered withK. bicoloratus, butP. cinnamomeus did not cluster withP. olivaceus, which is worth further studying.