DOI: 10.5061/dryad.5r59p06
title: Data from: Molecular operational taxonomic units reveal restricted geographic ranges and regional endemism in the Indo‐Pacific octocoral family Xeniidae

description: Aim: To quantify taxon diversity, biogeographic distributions and patterns
 of community assembly in xeniid octocorals using molecular operational
 taxonomic units (MOTUs). Location Red Sea, Indian and western Pacific
 Oceans. Taxon Xeniidae, a family of reef-dwelling octocorals (Anthozoa,
 Octocorallia). Methods Xeniids collected at 13 locations were sequenced at
 three barcode loci, and assigned to molecular operational taxonomic units
 (MOTUs) defined by minimum genetic distance thresholds. Taxon richness
 (no. of MOTUs) and endemicity (percent of MOTUs found at a single
 location) were quantified. Patterns of β-diversity (species turnover) and
 phylogenetic β-diversity (lineage turnover) among geographical regions
 were visualized using hierarchical clustering, NMDS plots, and
 distance-decay relationships. Community assembly was investigated by
 comparing the mean pairwise distance (MPD) and mean nearest taxon distance
 (MNTD) separating species in each assemblage to values generated for null
 communities. Results A genetic distance threshold of 0.3% discriminated 67
 MOTUs, with taxon richness ranging from 2-18 MOTUs per site. Out of the 67
 MOTUs, 48 (72%) were found at only a single location, and only two spanned
 both the western Indian and Pacific Oceans. Species turnover among sites
 was high, but phylogenetic β-diversity was lower than β-diversity and
 differed significantly from null models of community assembly at only two
 sites. β-diversity and phylogenetic β-diversity both increased
 significantly with geographic distance, and sites clustered into three
 distinct biogeographic regions (Red Sea and western Indian Ocean; Western
 Australia; western Pacific and Great Barrier Reef, Australia). All five
 major clades of xeniids were represented in each region. Main Conclusions
 A genetic approach to biodiversity estimation suggests that most xeniid
 taxa are regional endemics whose geographic distribution is likely
 governed by dispersal limitation. This conclusion contrasts with published
 records of certain morphospecies occurrences, which imply that they have
 broad geographic ranges. So far, the distribution of xeniid biodiversity
 mirrors that of scleractinian corals, with species richness highest in the
 Coral Triangle, but endemicity peaking in peripheral areas.
description: McFadden_suppl_164taxa_concatenated_alignmentAlignment of concatenated mtMutS + igr1 + COI + 28S rDNA barcodes for 164 taxa used to construct neighbor-joining tree (Kimura 2-parameter). Taxon abbreviations can be found in Appendix S1, Table S1 of the publication.McFadden_suppl_170taxa_concatenated_alignmentAlignment of concatenated mtMutS + igr1 + COI + 28S rDNA barcodes for 170 taxa used to construct maximum likelihood tree. Taxon abbreviations can be found in Appendix S1, Table S1 of the publication.McFadden_suppl_NJtree_164taxa_concatenatedgenesNeighbor-joining tree (Kimura 2-parameter) for 164 taxa constructed using concatenated mtMutS + igr1 + COI + 28S rDNA barcodes. Taxon abbreviations can be found in Appendix S1, Table S1 of the publication. With bootstrap percentages (1000 replicates). Newick format.McFadden_suppl_MLtree_170taxa_concatenatedgenesMaximum likelihood tree for 170 taxa constructed using concatenated mtMutS + igr1 + COI + 28S rDNA barcodes. Taxon abbreviations can be found in Appendix S1, Table S1 of the publication. GTR+I+G model of evolution with 100 bootstrap replicates. Saved as .tre format.pairwise_distance_matrix_ln(km)Matrix of pairwise great circle distances (ln(kilometers)) among sampled sites. Site abbreviations: ISR: Eilat, Israel; SAU: Saudi Arabia, central Red Sea; MAD: Nosy Bé, Madagascar; NIN: Ningaloo Reef, Western Australia; KIM: Kimberley, Western Australia; SUL: Lembeh Strait, Sulawesi, Indonesia; PAL: Republic of Palau; DON: Dongsha Atoll, Taiwan; GRE: Green (Ludao) Is., Taiwan; YON: Yonaguni Is., Ryukyu Archipelago, Japan; LIZ: Lizard Is., Queensland, Australia; COR: Coral Sea Islands Territory, Australia; HER: Heron Is., Queensland, Australia. Saved in .csv formatpairwise_diversity_and_distance_measuresPairwise values of compositional and phylogenetic beta-diversity indices among sampled sites. Indices were calculated using the 'betapart' R package (Baselga 2012).community_matrixPresence/absence matrix of molecular operational taxonomic units (MOTUs) by site. MOTUs determined by 0.3% genetic distance threshold. Site abbreviations: ISR: Eilat, Israel; SAU: Saudi Arabia, central Red Sea; MAD: Nosy Bé, Madagascar; NIN: Ningaloo Reef, Western Australia; KIM: Kimberley, Western Australia; SUL: Lembeh Strait, Sulawesi, Indonesia; PAL: Republic of Palau; DON: Dongsha Atoll, Taiwan; GRE: Green (Ludao) Is., Taiwan; YON: Yonaguni Is., Ryukyu Archipelago, Japan; LIZ: Lizard Is., Queensland, Australia; COR: Coral Sea Islands Territory, Australia; HER: Heron Is., Queensland, Australia.