Phylogeography of the manybar goatfish, Parupeneus multifasciatus, reveals isolation of the Hawaiian Archipelago and a cryptic species in the Marquesas Islands

To assess genetic connectivity in a common and abundant goatfish (family Mullidae), we surveyed 637 specimens of Parupeneus multifasciatus (Quoy and Gaimard, 1825) from 15 locations in the Hawaiian Islands plus Johnston Atoll, two locations in the Line Islands, two locations in French Polynesia, and two locations in the northwestern Pacific. Based on mitochondrial cytochrome b sequences, we found no evidence of population structure across Hawaii and the North Pacific; however, we observed genetic structuring between northern and southern Pacific locations with the equator-straddling Line Islands affiliated with the southern population. The Marquesas Islands sample in the South Pacific was highly divergent (d = 4.12% average sequence divergence from individuals from all other locations) indicating a cryptic species. These findings demonstrate that this goatfish is capable of extensive dispersal consistent with early life history traits in Mullidae, and provide further evidence for the biogeographic isolation of the Marquesas Islands.