Evolutionary relationships of Gadopsis spp. inferred from restriction enzyme analysis of their mitochondrial DNA

Gadopsis marmoratus and G. bispinosus are the sole members of an endemic Australian genus of percoid fishes. At least nine mitochondrial genotypes, identified by site polymorphisms for seven restriction enzymes, were found among 50 individuals from the two species sampled during this study. Net divergence between G. marmoratus and G. bispinosus was 6.60%, or at least 12.65 mutations. Mean divergence within G. marmoratus was 5.98%, or at least 12.29 mutations. The southern and northern forms of G. marmoratus are monophyletic taxa and the amount of divergence between the two forms confirms that a detailed taxonomic study is necessary to review the status of G. marmoratus. Despite detailed phytogenies constructed from restriction enzyme analysis of mitochondrial DNA, the relationship between G. bispinosus and the northern and southern forms of G. marmoratus was not resolved.