title: A revisited phylogeography of Nautilus pompilius.
abstract: The cephalopod genus Nautilus is considered a "living fossil" with a contested number of extant and extinct species, and a benthic lifestyle that limits movement of animals between isolated seamounts and landmasses in the Indo-Pacific. Nautiluses are fished for their shells, most heavily in the Philippines, and these fisheries have little monitoring or regulation. Here, we evaluate the hypothesis that multiple species of Nautilus (e.g., N. belauensis, N. repertus and N. stenomphalus) are in fact one species with a diverse phenotypic and geologic range. Using mitochondrial markers, we show that nautiluses from the Philippines, eastern Australia (Great Barrier Reef), Vanuatu, American Samoa, and Fiji fall into distinct geographical clades. For phylogenetic analysis of species complexes across the range of nautilus, we included sequences of Nautilus pompilius and other Nautilus species from GenBank from localities sampled in this study and others. We found that specimens from Western Australia cluster with samples from the Philippines, suggesting that interbreeding may be occurring between those locations, or that there is limited genetic drift due to large effective population sizes. Intriguingly, our data also show that nautilus identified in other studies as N. belauensis, N. stenomphalus, or N. repertus are likely N. pompilius displaying a diversity of morphological characters, suggesting that there is significant phenotypic plasticity within N. pompilius.
authors.affiliation: Friday Harbor Laboratories Biology Department University of Washington Seattle Washington.
authors.forename: Lauren E
authors.initials: LE
authors.lastname: Vandepas
authors.affiliation: Friday Harbor Laboratories Biology Department University of Washington Seattle Washington.
authors.forename: Frederick D
authors.initials: FD
authors.lastname: Dooley
authors.affiliation: Department of Biology Graduate Center City University of New York New York City New York 10016; Department of Biology Brooklyn College City University of New York Brooklyn New York 11210.
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Barord
authors.affiliation: Friday Harbor Laboratories Biology Department University of Washington Seattle Washington.
authors.forename: Billie J
authors.initials: BJ
authors.lastname: Swalla
authors.affiliation: Friday Harbor Laboratories Biology Department University of Washington Seattle Washington.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Ward
keywords: Indo‐Pacific; Nautilus pompilius; mitochondrial DNA; phenotypic plasticity; phylogeography