Spatial genetic subdivision between northern Australian and southeast Asian populations of Pristipomoides multidens: A tropical marine reef fish species

Abstract

Nucleotide sequence polymorphism in the left domain of the control region of the mitochondrial genome of over 700 goldband snapper (Pristipomoides multidens) was surveyed using both direct sequencing and innovative restriction enzyme cleavage analysis techniques. Southeast Asian populations were sampled adjacent to western Irian Jaya, northern Papua New Guinea and western Timor. Six Australian populations were sampled from adjacent to Exmouth in western Australia to Weipa in the northern Gulf of Carpentaria. The results show that significant genetic structure occurs among Indonesian and Australian waters along national boundaries; 14% of the total molecular variance among restriction site haplotypes was due to genetic distinction between Indonesian and Australian samples. Several lines of evidence suggest that gene flow does not occur freely along the northern and western Australian coastline, particularly on the northwestern Kimberley coast. Australian fisheries managers need to be alerted to the possibility of at least one genetically distinct population of this important commercial species which should be protected from over-harvesting that may otherwise lead to localised extinction and the erosion of genetic diversity. There is no convincing biological argument for the observed genetic disjunction in the Kimberley area. It may be due to the combined effect of past sea-level changes, sampling error or patterns of exploitation.