Phenotype and genotype differentiation between flathead grey mullet [Mugil cephalus] and thinlip grey mullet [ (Pisces: Mugilidae)]

Abstract

This study aimed to study the phenotype and genotype differentiation and to compare the amount of differences in phenotype based on morphometric character indices and meristic counts with the amount of differences in genotype based on random amplified polymorphic DNA (RAPD) fingerprinting between two Mugilidae, Flathead grey mullet (Mugil cephalus) and Thinlip grey mullet (Liza ramada). The results showed that there were significant differences in most of the morphometric character indices but no significant differences were detected in most of the meristic counts between M. cephalus and L. ramada. In addition, the euclidean distance between M. cephalus and L. ramada using hierarchical cluster analysis of quantitative phenotype based on morphometric character indices and meristic counts and condition factor was (0.421). Genotype analysis based on RAPD fingerprint showed highly genetic dissimilarity (0.437) between M. cephalus and L. ramada. These results confirmed that the amount of differences in genotype reflected the same amount of differences in phenotype between M. cephalus and L. ramada. Therefore, either phenotype analysis can be use based on a large number of morphometric character indices and meristic counts or genotype analysis based on RAPD fingerprinting to discriminate M. cephalus and L. ramada with the same results.

Key words: Phenotype, genotype, Mugil cephalus, Liza ramada.