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Aim Biodiversity patterns reflect both ecological and evolutionary processes interacting with geographical variation in climate and the current and historical connectivity between land areas. We sought to disentangle these effects in explaining the organization of ant diversity across geographical areas and islands in East Asia.Location The Japanese Archipelago including the Ryukyu and Ogasawara Islands, Taiwan and coastal continental regions of Korea, China and Russia.Methods We aggregated species occurrence records from published literature, specimen databases and museum records, and compiled climatic variables for islands and politically defined continental areas. Current and historical land connections in the Last Glacial Maximum were determined using bathymetric databases. We analysed factors driving patterns of Simpson composition dissimilarity using multiple regression of distance matrices.Results Temperature was the largest driver of dissimilarity among areas, with geographical distance and historical land contiguity also being important. Current land contiguity had no detectable effect. Main conclusionsWe found climate to be a primary driver of ant diversity patterns on large scales, consistent with previous work on ants and other organisms. Interestingly, land connectivity during historical periods of low sea level was more important than current land connectivity in explaining faunal similarities. This implies that despite the potential overwater dispersal of ants, overland dispersal via transient land connections is a more important driver of regional-scale biogeographical pattern in East Asia.

Population genetics of the coral genus Pocillopora have been more intensively studied than those of any other reef-building taxon. However, recent investigations have revealed that the current morphological classification is inadequate to represent genetic lineages. In this study, we isolated and characterized novel microsatellite loci from morphological Pocillopora meandrina (Type 1) and Pocillopora acuta (Type 5). Furthermore, we characterized previously reported microsatellite loci. A total of 27 loci (13 novel loci) proved useful for population genetic analyses at two sites in the Ryukyu Archipelago, in the northwestern Pacific. Clonal diversity differed in each genetic lineage. Genetic structure suggested by microsatellites corresponded to clusters in a phylogenetic tree constructed from a mitochondrial open reading frame (mtORF). In addition, we found an unknown mitochondrial haplotype of this mtORF. These microsatellite loci will be useful for studies of connectivity and genetic diversity of Pocillopora populations, and will also support coral reef conservation.

Coral−algae symbiosis represents the trophic and structural basis of coral reef ecosystems. However, despite global threats to coral reefs and the dependence of coral health and stress resistance upon such mutualisms, little is known about the community ecology of endosymbiotic Symbiodiniaceae. Concepts and methods from metacommunity ecology may be used to help us understand the assembly and stability of symbiont communities and the mutualisms they comprise. In this study, we sampled colonies of the symbiont-generalist coral Galaxea fascicularis in southwestern Japan and assessed the effects of environmental and host factors on Symbiodiniaceae community composition, while simultaneously exploring residual correlations among symbiont types that may reflect non-random assembly processes such as species interactions. We metabarcoded the Symbiodiniaceae ribosomal internal transcribed spacer 2 (ITS2) region and characterized the endosymbiotic community using 2 different OTU identity cutoffs , and analyzed them with generalized dissimilarity modeling and joint species distribution modeling. We found that Symbiodiniaceae form discrete communities characterized by the dominance of ITS2 types C1, C21a, or D1, that are each associated with a different suite of co-occurring background types and tend to exclude each other in an endosymbiotic community. The communities showed modest responses to temperature, water depth, host genotype, polyp size, and bleaching status, and there was local sequence variation within the ITS2 types. After accounting for the effects of those variables, residual correlations remained in community composition, pointing to the possibility that Symbiodiniaceae community assembly in corals may be structured by interspecific competitive or facilitating interactions rather than only exogenous variables.

Flagellariaceae are grass relatives that climb using leaf-tip tendrils in palaeotropical rainforests. As the sister group to Joinvilleaceae, Ecdeiocoleaceae and Poaceae, they could be indicative of the ancestral habitat of the graminid clade. Although four species are usually accepted in this monogeneric family, Flagellaria has never been revised taxonomically and species delimitation is understood poorly, especially for the Pacific. Here, we document the morphological variation in the genus, and explore phylogenetic patterns by maximum likelihood analysis (GARLI) and Bayesian inference (MrBayes) of the internal transcribed spacer (ITS) of the nuclear ribosomal repeat and the plastid matK, psbA–trnH and rps16 regions. Ecological variation was inferred from climatic factors evaluated by MaxEnt analysis. We show that Flagellaria is more diverse than previously thought, and describe one new species in Fiji (Flagellaria collaris Wepfer & H.P.Linder) and three new varieties in F. indica (vars. australiensis, bifurcata, borneensis). Flagellaria is most diverse in the Pacific islands, where Fiji harbours three of the five species.