Global-scale genetic structure of a cosmopolitan cold-water coral species

1.When considering widely distributed marine organisms with low dispersal capabilities, there is often an implication that the distribution of cosmopolitan species is an artefact of taxonomy, constrained by the absence of characters for delimiting either sibling or cryptic species. Few studies have assessed the relationship among populations across the global range of the species' distribution, and the presence of oceanographic barriers that might influence gene flow among populations are underestimated. 2.In this study, evolutionary and ecological drivers of connectivity patterns have been inferred among populations of the cold-water coral Desmophyllum dianthus, a common and widespread solitary scleractinian species, whose reproduction strategy and larval dispersal are still poorly unknown. 3.The genetic structure of D. dianthus was explored using 30 microsatellites in 347 specimens from 13 localities distributed in the Mediterranean Sea and Atlantic and Pacific Oceans. 4.Results clearly reveal genetically differentiated populations in the Northern and Southern Hemispheres (F = 0.16, F = 0.01, F = 0.15, P-values highly significant), and Chilean and New Zealand populations with independent genetic profiles. 5.Marine connectivity patterns at different spatial scales are discussed to characterize larval dispersal and gene flow through the Northern and Southern Hemispheres.
This research was supported by the Spanish Ministry of Science and Innovation (CGL2011‐23306), and EU CoCoNET—“Towards COast to COast NETworks of marine protected areas (from the shore to the high and deep sea), coupled with sea‐based wind energy potential”—from FP7‐KKBE of the European Commission (project ID: 287844). This scientific contribution commits to EESF Cocarde, Italian Flag Ritmare, and Region Apulia Biomap programmes. This is scientific publication no. 1888 Ismar‐CNR Bologna. Funding to VH was partially provided through Fondecyt project nos. 1131039 and 1161699.