Table 1.
Summary of the population structure of hydrothermal vent organisms living in the Southwest Pacific Ocean.
Different shade indicates population differentiation based on cytochrome oxidase subunit I (COI) sequences of individuals from distinct geographical regions.
Fig 1.
Map of A. alayseae sampling locations in the Southwest Pacific Ocean and a photograph of a hydrothermal vent in the North Fiji Basin and its associated biological communities.
(A) Sampling locations of A. alayseae. Lines represent subduction zones. Red circles indicate sampling areas. Some sampling sites located short distances (<5 km) from each other (R1968-C6 and R1970-C3, R1964-C1 and 1966-C11, TA25A and TA25D) are marked with single circle. (B) An active vent at the 1970-C3 sampling site in the North Fiji Basin. The dominant visible taxa in the image are the provannid snail Ifremeria nautilei (center bottom and right) and the balanomorph barnacle Eochionelasmus ohtai (left). A small cluster of mytilid mussels, Bathymodiolus sp., and alvinocaridid shrimp species are visible. Scattered individuals of the bythograeid crab A. alayseae are generally seen in association with I. nautilei and E. ohtai.
Table 2.
Sampling information for bythograeid crabs collected from hydrothermal vent regions in the Southwest Pacific Ocean.
Table 3.
Primers used for PCR amplification.
Fig 2.
Phylogenetic tree of bythograeid crabs, constructed using a concatenated dataset of COI, 16S rRNA, and 28S rRNA genes.
The gray-shaded box highlights three Austinograea alayseae populations. Numbers at internodes are the maximum likelihood bootstrap proportions (left) and Bayesian posterior probabilities (right). Asterisks indicate bootstrap values <60%.
Table 4.
Intra- and interspecies variations in COI, 16S rDNA, and 28S rDNA sequences of Bythograeidae.
Sequence variations were calculated from the nucleotide sequences using the p-distance method in MEGA X.
Table 5.
Variation among COI nucleotide sequences of the bythograeid crab Austinograea alayseae collected from three back-arc basins in the Southwest Pacific Ocean.
Fig 3.
Median-joining network based on COI haplotypes from the bythograeid crab Austinograea alayseae collected from hydrothermal vent fields in the Southwest Pacific Ocean.
Circle size and color reflect haplotype frequency and vent field, respectively. The number of short bars on each branch indicates the number of nucleotide substitutions between haplotypes.